What steel are springs made from?

GOST 13764-86 helical cylindrical compression and tension springs made of round steel. classification

GOST 13764-86

INTERSTATE STANDARD

HELICAL CYLINDRICAL COMPRESSION AND EXTENSION SPRINGS

ROUND STEEL

CLASSIFICATION

Moscow

Standardinform

2007

INTERSTATE STANDARD

Date of introduction 07/01/88

This standard applies to springs intended for operation in non-aggressive environments at temperatures from minus 60 °C to plus 120 °C.

1. Springs are divided into classes, types and categories in accordance with those indicated in the table. 1 and 2.

Table 1

Spring class	Type of springs	Loading	Endurance Nf (established trouble-free operating time), cycles, not less	Inertial collision of turns
I	Compression and stretching	Cyclic	1 × 107	Absent
II	Compression and stretching	Cyclic and static	1 × 105	Absent
III	Compression	Cyclic	2 × 103	Allowed

Notes:

1. The absence of collision of coils of compression springs is determined by the condition:

where v max is the highest speed of movement of the moving end of the spring during loading or unloading, m/s;

vк is the critical velocity of the compression spring (corresponds to the occurrence of collision of the coils of the spring due to inertia forces), m/s.

2. Endurance ratings do not apply to extension spring hooks.

3. The criteria for failure under operating conditions is failure to comply with the requirements of GOST 16118.

The class of springs characterizes the loading and endurance conditions, and also determines the basic requirements for materials and manufacturing technology.

Spring discharges reflect information about force ranges, grades of spring steels used, as well as standards for permissible stresses.

(Changed edition, Amendment No. 1).

2. The standard includes additional requirements, which are given in Appendices 1 - 3.

Brief information about the endurance and durability of cyclic and static springs

When determining the dimensions of the springs, it is necessary to take into account that at vmax > vк , in addition to tangential torsional stresses, contact stresses arise from the collision of coils moving by inertia after the parts mating with the springs have slowed down and stopped. If there is no collision of turns, then springs with low voltages t3 have the best endurance, i.e. springs of class I, intermediate - cyclic springs of class II and the worst - springs of class III.

In the presence of intense collision of turns, endurance is in the reverse order, i.e. increases not with a decrease, but with an increase in t3. Resilience is in the same order, i.e. reduction of residual deformations or settling of springs during operation.

The means of regulating the endurance and durability of cyclic springs within each class at constant specified values ​​of the working stroke are changes in the difference between the maximum shear stress during torsion t3 and the shear stress during working deformation t2.

An increase in the difference t3 - t2 causes an increase in the endurance and durability of cyclic springs of all classes while simultaneously increasing the size of the units. A decrease in the difference t3 - t2 is accompanied by reverse changes in the service qualities and sizes of spaces in the mechanisms for placing springs.

For class I springs, the design stresses and properties of the metal are regulated so that at vmax / vк £ 1, the standard endurance of the springs under the action of force F1 (spring force during preliminary deformation) is ensured for all feasible locations and sizes of working sections on the force diagrams (stress differences t3 - t2 and t2 - t1, where t1 is the shear stress during preliminary deformation).

Class II cyclic springs with vmax / vк £ 1, depending on the location and size of the working sections, can be subjected to conditions of both unlimited and limited endurance.

Class III cyclic springs with all ratios vmax / vк and values ​​of the relative inertial gap of springs d no more than 0.4 [formula (1) GOST 13765] are characterized by limited endurance, since they are designed for extremely high tangential torsional stresses, to which at vmax / vк > 1, contact stresses from the collision of turns are added.

Static springs that remain in a deformed state for a long time and are periodically loaded at a speed vmax less than vk belong to class II. The limitations on design stresses and wire properties introduced by the standard (GOST 13764, Table 2) ensure unlimited resistance of static springs with residual deformations of no more than 15% of the maximum deformation s3 .

The permissible residual deformations of static springs are regulated by the coordination of the spring forces at the working deformation s3 on the force diagrams, and an increase in the difference F3 - F2 helps to reduce the residual deformations.

Technological means of regulating the endurance and resistance of springs are determined by the technical specifications documentation.

Brief information about materials

The spring steel grades available in industry are characterized by the following properties and conditions of use.

Wire of class I according to GOST 9389. High tensile strength. The presence of large residual stresses of the first kind (from drawing and winding) causes the appearance of residual deformations of springs at stresses t3 > 0.32 Rm. At vmax > vк , residual deformations are high, regardless of the use of the captive operation. In connection with the above, class I wire according to GOST 9389 is prescribed for class III springs in the form of three-core cables.

Wire of classes II and IIA according to GOST 9389. Differs from wire of class I in reduced tensile strength and increased ductility. It is used for products operating at low temperatures, as well as for tension springs with complex hook designs. Class IIA wire differs from class II wire in higher dimensional accuracy, a reduction in harmful impurities in the metal and a further increase in ductility.

Steel grade 65G. Increased tendency to form hardening cracks. It is used to reduce the cost of production for mass-produced products in cases where spring failures do not cause disruption in the functioning of mechanism parts and are not associated with labor-intensive replacements.

Steel grade 51HFA. Increased heat resistance. Hardened to a hardness of no more than 53.5 HRCe. As a result of its high elastic and viscous properties, it is the best material for class I springs.

Steel grades 60С2А, 60С2. High elastic and viscous properties. Increased tendency to graphitization and insufficient hardenability for sections d > 20 mm. Wide applicability for class I and II springs. For class III springs it is assigned at vmax £ 6 m/s.

Steel 60S2HFA. High hardenability, low tendency to grain growth and decarburization when heated (compared to 60C2A steel), increased toughness, heat resistance and cold resistance, good cyclic strength and relaxation resistance in a wide range of cyclic temperature changes. Preferred use in wire sections of 30 mm and above.

Steel grade 65S2VA. High elastic properties and viscosity. Increased hardenability. Serves as the best material for class III springs. Applicable for vmax > 6 m/s.

Steel grade 70С3А. Increased hardenability. Has a tendency to graphitize. Preferred use with wire diameters d ³ 20 mm. The substitute is steel 60S2N2A.

Note. The predominant practical use of springs made from 51KhFA steel is determined by the temperature range from minus 180 to plus 250 °C, from 60S2KhFA steel from minus 100 to plus 250 °C, from class IIA wire according to GOST 9389 from minus 180 to plus 120 °C, from steel grades 65G, 70S3A, 60S2A, 65S2VA and class I wire according to GOST 9389 from minus 60 to plus 120 °C. In cases where springs are used at higher temperatures, it is recommended to take into account the temperature changes of the module.

(Changed edition, Amendment No. 1).

Brief information about the purpose of high hardness for class III springs

It has been established that compression springs operating in the mode of intense collision of coils fail prematurely, mainly due to breakage of the supporting coils, as well as due to the rapid loss of force as a result of residual deformations.

The purpose of high hardness contributes to an increase in the elastic properties and tensile strength Rm of spring materials, as a result of which residual deformations are sharply reduced and, thanks to this, the springs operate for a longer time without breakdowns and without unacceptable losses of force.

For the steel grades used, the hardness range HRCе 53.5–58.0 is safe for the performance of class III springs, but the condition for this is the mandatory use of shot blasting, regardless of the required endurance standards.

An important prerequisite for assigning high hardness is also the complete reduction of heating periods for hardening and setting the duration of tempering for a given hardness to at least 45 minutes when heated in liquid baths and at least 1 hour when heated in air.

All springs that are hardened to high hardness, depending on the level of requirements for stability of dimensions and forces, as well as in order to control metal defects, are recommended to be subjected to bondage until the coils come into contact, also to a piledriver or bench hammer.

INFORMATION DATA

1. DEVELOPERS

B.A. Stankevich (topic leader); HE. Magnitsky , Dr. tech. sciences; A.A. Kosilov; B.N. Kryukov; E.A. Karashtin , Ph.D. tech. sciences

2. APPROVED AND ENTERED INTO EFFECT by Resolution of the USSR State Committee on Standards dated December 19, 1986 No. 4007

3. The standard fully complies with ST SEV 5616-86

4. INSTEAD GOST 13764-68

5. REFERENCE REGULATIVE AND TECHNICAL DOCUMENTS

6. The validity period was lifted according to Protocol No. 7-95 of the Interstate Council for Standardization, Metrology and Certification (IUS 11-95)

7. EDITION (January 2007) with Change No. 1, approved in November 1988 (IUS 2-89)

CONTENT

Source: https://files.stroyinf.ru/Data2/1/4294837/4294837574.htm

Spring steel

Many elastic elements play a key role in the operation of various components and mechanisms. During operation, they are subjected to numerous alternating loads, under the influence of which they are reversibly deformed, returning to their original shape and dimensions after completion of the load. A characteristic difference between their functioning is that under significant static and impact impacts they receive only elastic deformation, and residual deformation does not occur.

What is spring steel?

Spring steel is a medium or high carbon steel with a low volume of alloying elements (up to 2.5%), but a significant yield strength. This determines the property of products made of such metal to acquire their original shape, despite significant bending, fracture, torsion and dynamic loading. This feature is used in the production of spring products, metal swords, piano strings and spring clamps.

Hardening of spring steel followed by tempering at 400-500 °C to a value of 45 HRC are mandatory production stages. Springs made from improperly hardened material become brittle and crumble easily. The heat treatment of spring steels in many industries has been thoroughly mastered by thermists and is carried out in accordance with the regimes regulated in the standards.

The main requirements that are set for spring steels and alloys are to ensure increased indicators of flexibility, ductility, endurance, resistance to brittle fracture, and resistance to stress weakening. This is achieved to a greater extent due to the addition of alloying elements.

Silicon is a fundamental component of steel alloys of this type. Melting in ferrite, it contributes to the formation of persistent heterogeneity of carbon atoms that delay dislocation.

In parallel with the increase in the hardness of the alloy, silicon significantly reduces its ductility and causes decarburization, which greatly limits the use of inexpensive, pure silicon alloys.

Properties and applications of spring steel

The presence of silicon in different spring steels is 0.17-2.60% depending on the class.

In addition, chromium and manganese are considered useful alloying additives in cumulative alloying, since they increase resistance to low plastic deformations, while simultaneously increasing many of the technological properties of the alloy.

The addition of vanadium, molybdenum and tungsten inclusions ensures the formation of a stable thin homogeneous structure and a carbide fraction that blocks dislocation. To improve the technical and operational properties, microdoses of boron are introduced into the steel composition.

Spring steel grades 70SZA and 60S2XA are distinguished by their maximum physical and mechanical properties. Their elasticity parameters reach 1100 MPa, and their hardness is up to 48 HRC on the Rockwell scale.

With these indicators, the metal is sensitive to stress concentrators (surface defects). In their absence, the parameters of the metal’s endurance in bending are above 550 MPa, and in torsion – 350 MPa.

To reduce this sensitivity, finished products receive external oaklen by blasting with shot. As a result of such hardening, endurance indicators increase by 2 times.

Stainless steel wire is used for the manufacture of compression, tension and torsion springs, which are used without insulation in distillate, water-steam environment, saline, alkaline and alcohol solutions, and sea water. This wire is optimally suited for the production of springs used in the chemical and food industry, for operation in the temperature range of −250 °C + 250 °C.

Structural spring steel 65g is most widely used in the production of elastic parts of various mechanisms (springs, springs and washers) due to its low cost, increased hardness and elasticity. The only drawback limiting its use in instrument making is its low fatigue strength (less than 200,000 cycles). Steel of this grade has an unhardened hardness of 25 HRC, after hardening it increases to 61 HRC.

Alloy spring steel 60s2a is characterized by low cost, high elasticity, wear resistance, and lack of temper brittleness. This metal is not afraid of deformation from physical and mechanical contacts and pressure. It does not require a protective coating and can be used effectively in normal humidity. The maximum temperature for its use is no more than 250 ºС. Used in the production of a variety of rolled metal products.

Spring sheet steel is relevant in the production of marine, food and medical equipment, where the working environment requires increased corrosion resistance. This steel is slightly inferior in strength to stainless steel.

The corrosion resistance of spring stainless steels is associated with increased levels of chromium and molybdenum. In addition, they combine excellent resistance to cracking under load and significant physical and mechanical strength.

Welding spring steel has its challenges. As a rule, the metal is pre-strengthened by a thermal method, and during welding this hardening is destroyed.

A solution to the problem can be welding with an appropriate ferrite electrode through preheating and further tempering to prevent cracks in the thermally affected area.

When welding with austenitic electrodes based on stainless steel or nickel, the risk of cracking is reduced due to the increased solubility of hydrogen and the good ductility of the melting metal.

An alphanumeric marking system for spring steel has been officially adopted. The main alloying additives have a special letter code. The numerical designation shows the percentage level of a particular element. If the amount of an individual component does not exceed 1.5%, then the number after the letter index is not indicated. The carbon level is displayed at the beginning of the code in hundredths of a percent.

Source: https://promplace.ru/metallicheskie-izdeliya-i-konstrukcii-staty/pruzhinnaya-stal-1497.htm

What steel are springs made from?

g84jsm9tB4S

Structural carbon or high-carbon steel includes spring steel. To give it highly targeted properties, it is doped in small quantities with 2-3 elements, for a total of up to 2.5%. But the use of these steel grades is not limited to the manufacture of springs. This group is called that because the name most strongly reflects their main feature - elasticity.

Characteristics of spring steels

Spring steels are characterized by increased yield strength (δB) and elasticity. This is the most important characteristic of metal - to withstand mechanical loads without changing its original shape. Those. a metal subjected to tension or, conversely, compression (elastic deformation), after removing the acting forces from it, must remain in its original shape (without residual deformation).

Types and scope of spring steel

Based on the presence of additional properties, spring steel is divided into alloy (stainless) and carbon. Alloy steel is based on carbon steel with a C content of 65-85% and is alloyed with 4 main elements, all or selectively, each of which brings its own characteristics:

Chromium - at a concentration of more than 13%, works to ensure the corrosion resistance of the metal. With a chromium concentration of about 30%, the product can work in aggressive environments: acidic (except sulfuric acid), alkaline, aqueous. Corrosion spring steel is always alloyed with a second accompanying element - tungsten and/or manganese. Operating temperature up to 250 °C.

Tungsten is a refractory substance. When its powder gets into the melt, it forms numerous crystallization centers, crushing the grain, which leads to increased plasticity without loss of strength. This brings its advantages: the quality of such a structure remains very high during heating and intense abrasion of the surface.

During heat treatment, this element retains its fine-grained structure and eliminates softening of steel during heating (during operation) and dislocation.

During hardening, it increases hardenability, as a result of which the structure becomes homogeneous to a greater depth, which in turn increases the service life of the product.

Manganese and silicon usually participate in mutual doping, and the ratio always increases in favor of manganese, up to about 1.5 times. That is, if the silicon content is 1%, then manganese is added in an amount of 1.1-1.5%.

Refractory silicon is a non-carbide-forming element. When it enters the melt, it is one of the first to take part in crystallization, pushing carbon carbides to the grain boundaries, which accordingly leads to strengthening of the metal.

Manganese can be called a structure stabilizer. By simultaneously distorting the metal lattice and strengthening it, manganese eliminates the excessive strength of silicon.

In some steel grades (when the product is operating in high-temperature conditions, at temperatures above 300 ºC), nickel is added to the steel. It eliminates the formation of chromium carbides along grain boundaries, which lead to matrix destruction.

Vanadium can also be an alloying element, its function is similar to that of tungsten.

Source: https://pechi-sibiri.ru/iz-kakoj-stali-delajut-pruzhiny/

Stainless steel spring sheet

• Aluminium, duralumin
• Copper, bronze, brass
• Tin
• Lead
• Zinc

When it enters the melt, it is one of the first to take part in crystallization, pushing carbon carbides to the grain boundaries, which accordingly leads to strengthening of the metal. Operating temperature up to 250 °C.

The product is shaped in an annealed state, when the steel has the maximum possible softness, after which it is heated to 830-870 C and cooled in an oil or water environment (only for grade 60 CA). Production. When its powder gets into the melt, it forms numerous crystallization centers, crushing the grain, which leads to increased plasticity without loss of strength.

In some steel grades (when the product is operating in high-temperature conditions, at temperatures above 300 ºC), nickel is added to the steel.

They are used wherever there is a need to provide the product with elasticity, ductility and strength at the same time. Spring brands specify the element copper; its content should not exceed 0.15%. Marking. Manganese and silicon usually participate in mutual doping, and the ratio always increases in favor of manganese, up to about 1.5 times.

This group is called that because the name most strongly reflects their main feature - elasticity. Structural carbon or high-carbon steel includes spring steel.

Alloy steel is based on carbon steel with a C content of 65-85% and is alloyed with 4 main elements, all or selectively, each of which brings its own characteristics: Chromium - at a concentration of more than 13%, it works to ensure the corrosion resistance of the metal.

Stainless steel spring sheet

Let's look at the example of 60S2KhFA: 60 is the percentage of carbon in tenths (carbon is not indicated in the letter value), C2 is the letter designation of silicon with index 2, denotes a 2-fold increase in the standard content (1-1.5%), X is the presence chromium up to 0.9-1%, F - tungsten content up to 1%, A - the added letter index A at the end of the marking indicates the minimum content of harmful impurities of phosphorus and sulfur, no more than 0.015%.

By simultaneously distorting the metal lattice and strengthening it, manganese eliminates the excessive strength of silicon. Many of them experience loads that periodically replace each other, and with a huge cyclic frequency. Since copper, being a low-melting substance, concentrates at the grain boundaries, reducing strength. Manganese can be called a structure stabilizer.

Depending on further processing and the final type of part, steel is supplied in sheets, wire, hexagons, and squares.

With a chromium concentration of about 30%, the product can work in aggressive environments: acidic (except sulfuric acid), alkaline, aqueous. During hardening, it increases hardenability, as a result of which the structure becomes homogeneous to a greater depth, which in turn increases the service life of the product.

All requirements and recommendations for this type of steel are described in GOST. Based on them, the company develops more detailed technological sheets that meet narrow parameters. The same applies to the ends of the spring: they serve as attachment points, which increases the load in these and adjacent places. The same applies to gears, flanges, washers, collets, etc.

Without exception, all spring steels are subjected to thermomechanical treatment.

To give it highly targeted properties, it is doped in small quantities with 2-3 elements, for a total of up to 2.5%. This is the most important characteristic of metal - to withstand mechanical loads without changing its original shape. Spring steel grades - properties and scope of application. That is, if the silicon content is 1%, then manganese is added in an amount of 1.1-1.5%.

High performance qualities of the product are ensured by 2 components: the structure of the metal, which is determined by the chemical composition and subsequent processing, the presence of non-metallic inclusions in the structure, or rather the minimum quantity and size, which is eliminated at the stage of smelting and casting, the shape of the part (spiral, arc) and its dimensions, which is determined by the calculation method.

Thermo-mechanical treatment. Brands and areas of application of spring steel. Spring brands include: 50HG, 3K-7, 65G, 65GA, 50HGFA, 50HFA, 51HFA, 50HSA, 55S2, 55S2A, 55S2GF, 55HGR, 60G, 60S2, 60S2A, 605, 70, 70G, 75, 80, 85, 60С2ХА , 60S2HFA, 65S2VA, 68A, 68GA, 70G2, 70S2XA, 70S3A, 70HGFA, SH, SL, SM, DM, DN, KT-2.

Based on the presence of additional properties, spring steel is divided into alloy (stainless) and carbon.

But the use of these steel grades is not limited to the manufacture of springs. Vanadium can also be an alloying element, its function is similar to that of tungsten. Those.

a metal subjected to tension or, conversely, compression (elastic deformation), after removing the acting forces from it, must remain in its original shape (without residual deformation). The resulting martensite is tempered at a temperature of 480 ºC.

It eliminates the formation of chromium carbides along grain boundaries, which lead to matrix destruction. With this dynamic of increased aging and wear, stronger steel (with less elasticity) is susceptible to rapid aging and sudden failure.

They are used on such objects as railway transport. Tungsten is a refractory substance. Marking of spring steels is carried out as follows. Refractory silicon is a non-carbide-forming element.

These are: bearing housings, which experience compression and tension at each point with high frequency, friction discs, which experience dynamic loads and compression, thrust washers, most of the time they experience compression loads, but a sharp change in tension can also be added to them, brake bands , for which one of the main tasks is elasticity under repeated stretching. Characteristics of spring steels.

When the spring is stretched, the inner and outer sides of the coils experience different degrees of stress: the outer ones are less susceptible to stretching, while the inner ones experience the greatest degree of deformation. Spring steels are characterized by increased yield strength (δ B) and elasticity. All parts made from these grades are subject to tension and compression.

Therefore, steel grades have been developed that are preferably used for compression or tension.

Spring-spring steels can be grouped by position: unalloyed with a carbon content of 65-85% - inexpensive general purpose steel, manganese-silicon - the cheapest with high physical and chemical properties, chromium-manganese - stainless steel, works in aggressive environments at t - 250 +250 C, additionally alloyed with tungsten, vanadium, boron - these are steels with an increased service life due to their homogeneous structure, excellent strength-ductility ratio due to crushed grains and can withstand high mechanical loads. During heat treatment, this element retains its fine-grained structure and eliminates softening of steel during heating (during operation) and dislocation. Corrosion spring steel is always alloyed with a second accompanying element - tungsten and/or manganese.

Grades of such steel are used for the manufacture of not only springs and leaf springs, although this is their main purpose, which characterizes the main property. This brings its advantages: the quality of such a structure remains very high during heating and intense abrasion of the surface. After it, strength and wear resistance can increase 2 times.

see also

• STAINLESS SHEET MIRROR STEELIt is very loved by modern designers and architects. Concept and types of mirror stainless steel sheet. This type of rolled metal is made from stainless steel
• STAINLESS STEEL FOOD SHEETFood grade stainless steel is used not only in kitchens and catering establishments, it has also found application in the chemical and oil industries, in
• STAINLESS SHEET STEEL FOOD PRICE Application of food steel. Its feature is increased corrosion resistance, due to which the material can be in contact with food for a long time.
• DECORATIVE STAINLESS STEEL SHEETPestovo, ow. 7, processing of my personal data specified in this appeal (collection, recording, systematization, accumulation, storage, clarification
• BUY STAINLESS STEEL SHEET 2 MM You can buy stainless steel sheet 2 mm thick on this website at an affordable price right now. Heat exchangers, containers,

Source: https://trastmetal.ru/blog/stal-pruzhinnaja-listovaja-nerzhavejushhaja

Spring steel grades - properties and scope of application

Structural carbon or high-carbon steel includes spring steel. To give it highly targeted properties, it is doped in small quantities with 2-3 elements, for a total of up to 2.5%. But the use of these steel grades is not limited to the manufacture of springs. This group is called that because the name most strongly reflects their main feature - elasticity.

Marking

Spring-spring steels can be grouped by position:

• unalloyed with a carbon content of 65-85% - inexpensive general purpose steel;
• manganese-silicon - the cheapest with high physical and chemical properties;
• chrome-manganese - stainless steel, works in aggressive environments at t -250 +250 C;
• additionally alloyed and/or tungsten, vanadium, boron - they are steels with an increased service life due to their homogeneous structure, an excellent strength-to-ductility ratio due to fine grains and can withstand high mechanical loads. They are used on such objects as railway transport.

Marking of spring steels is carried out as follows. Let's look at the example of 60S2HFA:

• 60 - percentage of carbon in tenths (carbon is not indicated in a letter value);
• C2 - letter designation of silicon with index 2, indicates a 2-fold increase in the standard content (1-1.5%);
• X - presence of chromium up to 0.9-1%;
• F - tungsten content up to 1%;
• A - the added letter index A at the end of the marking indicates the minimum content of harmful impurities of phosphorus and sulfur, no more than 0.015%. 

Production

Depending on further processing and the final type of part, steel is supplied in sheets, wire, hexagons, and squares. High performance qualities of the product are ensured by 2 components:

1. the structure of the metal, which is determined by the chemical composition and subsequent processing;
2. the presence of non-metallic inclusions in the structure, or rather the minimum quantity and size, which is eliminated at the stage of smelting and casting;
3. the shape of the part (spiral, arc) and its dimensions, which is determined by the calculation method.

When the spring is stretched, the inner and outer sides of the coils experience different degrees of stress: the outer ones are less susceptible to stretching, while the inner ones experience the greatest degree of deformation. The same applies to the ends of the spring: they serve as attachment points, which increases the load in these and adjacent places. Therefore, steel grades have been developed that are preferably used for compression or tension.

Thermo-mechanical treatment

Without exception, all spring steels are subjected to thermomechanical treatment. After it, strength and wear resistance can increase 2 times. The product is shaped in an annealed state, when the steel has the maximum possible softness, after which it is heated to 830-870 C and cooled in an oil or water environment (only for grade 60 CA). The resulting martensite is tempered at a temperature of 480 ºC.

Source: https://prompriem.ru/stati/pruzhinnaya-stal.html

What kind of steel is in the spring?

Car springs make very high-quality knives that are durable and wear-resistant. For this reason, they have become widespread among professional craftsmen. A properly made knife from a spring can withstand heavy loads and can be used for its intended purpose. Learning all the intricacies of creating this blade will help you avoid mistakes and make a truly high-quality knife.

Peculiarities

To understand how to make a knife from a spring, you definitely need to study the characteristics of the material. Steel has increased wear resistance, good ductility, toughness, and resistance to impact loads. The listed characteristics are necessary for such knives as hunting, tourist, army, kitchen and machetes.

The popularity of products made from springs is also associated with the availability of the material - it can be found in almost any garage. For processing you will need a minimum of tools. Most often, blades are made of 65G steel, less common are options from 50KhGSA and 50KhGA - the difference between the three options will be invisible and will not affect the properties of the product in any way.

Manufacturing stages

Since the material is not the most suitable form for the workpiece, it is necessary to work on it with a forge hammer or grinder to give the required thickness of 3-6 mm (depending on the type of product).

The first stage in making a knife from spring steel is relieving the internal stress of the metal. To do this, it needs to be heated to a temperature of 420-460 degrees Celsius and, without removing it from the forge, allowed to cool.

In the absence of a thermometer, the preparation is done by eye, that is, until the redness is completely uniform.

The principle should be adhered to: it is better not to overheat the steel, but experimentally, checking the properties of the material after each tempering, increase the time until a state is reached in which the steel acquires the desired ductility.

After the vacation procedure, you can begin metalwork. If there is no special professional tool, a manual one is used - with it more time will be spent on giving the desired shape to the workpiece. Having achieved the correct parameters of the blade using an anvil and grinding tools, it is necessary to carry out hardening - then the spring steel for knives will return its previous properties.

Materials and tools

Almost any car spring is suitable for making a blade, but it is advisable to use a spare part from a truck. The knife handle is made of material chosen by the master. It can be wood, plastic, plexiglass and so on. Mechanical work on making a knife from spring steel is best carried out using equipment that helps speed up the production process:

• angle grinder (grinder);
• drill or drilling machine;
• files and sandpaper of different grain sizes;
• blacksmith's forge, anvil, hammer;
• oil for quenching and steel tempering furnace;
• knife sharpening machine.

To make knives from spring steel, it is not necessary to use a professional tool - you can always find an alternative and create a high-quality product in artisanal conditions. In the absence of the devices listed above, you can use improvised means: a hacksaw, a file, a regular oven or a fire for hardening and tempering.

Blade

Its size and shape depend on what type of knife you plan to get (military, kitchen, hunting, tourist, and so on). Before starting blacksmithing and metalworking work, the steel must be released - after this the metal will be easy to process.

If a person does not use a blacksmith’s hammer and anvil, you can cut out the workpiece with a grinder or a hacksaw. The spring steel for the knife must be cooled during operation so as not to overheat it.

In the place of the workpiece where the handle elements will be attached, you need to drill holes, then insert the fastening pins into them.

We draw out the shape of the blade more carefully. We remove excess from the shank. An example of a blade after processing.

Lever

The design of a knife handle is a separate and highly individual topic for craftsmen. When making it, everyone relies on their own aesthetic taste and puts all their professionalism into the work.

For beginners, it is recommended to use the classic version of the handle. It can be made of two wooden or plastic dies with blind holes on the inside for pins.

The shape of the dies is adjusted to the size of the owner’s hand. The process is carried out in assembled form (the products are temporarily attached to the blade).

After the knife has gone through the stages of hardening and tempering, and the dies of the handle have been brought to the desired shape, they must be placed on glue. Thanks to the pins installed in the blade, they will hold securely. The parts to be glued must be clamped with a clamp or vice for better adhesion.

We make square inserts from leather. We cut a wooden block into two parts. We attach leather inserts to the middle of the handle and make blanks. We cut holes in them. We process the handle. The classic version of the handle.

Hardening

Steel hardening is the most important stage in production. Without it, it is impossible to obtain a full-fledged product, since before metalworking begins, the internal stress of the metal is removed, and it loses its characteristics.

It’s easy to harden forged spring knives with your own hands. You can even use a regular fire made from coal, but it is advisable to do this using a blacksmith's forge.

The product must be heated to 840-880 degrees Celsius or, if there is no thermometer, to a temperature at which a magnet will not be attracted to it.

There are two options for hardening: heating only the cutting edge or the entire blade. There is no practical need to use the latter method. Spring steel is quite elastic and durable, and in the area of ​​the knife handle it is not subject to increased exposure to heavy loads.

In addition, at home it can be problematic to heat the entire area of ​​the workpiece to a high temperature, so it is advisable to use the first option. Having dipped the heated metal into used machine or vegetable oil, remove it and let it cool.

After hardening the steel, it is necessary to conduct a low tempering - heat it to 160-200 degrees Celsius. A fire, stove, and even an ordinary oven are suitable for these purposes. After all actions, the metal must be allowed to cool slowly.

Sharpening

It is advisable to perform the procedure using a special device that allows you to adjust and fix the angle of the workpiece relative to the grindstone. A file and a regular abrasive wheel are suitable for these purposes. During the first sharpening, the blade cross-section is formed - this must be done before the hardening procedure.

The master can choose one of the most common types of sections: flat-concave, flat-concave, wedge-shaped. After initial sharpening, hardening and tempering of the steel, you can carry out grinding work and attach the knife handle, and then bring the blade to the required sharpness. If done correctly, spring steel for knives will remain sharp for a very long time.

The final stage will be polishing the entire surface of the blade to give it a mirror shine.

Source: https://varimtutru.com/kakaya-stal-v-ressore/

Features of Stainless Spring Steel

Stainless spring steel is used for the production of elastic elements and parts of mechanisms and machines that experience repeated variable loads during operation. Examples of such steels are the alloys of the AISI 304 and AISI 321 series. You can order spring stainless steel at specialized metal warehouses.

Technical requirements for stainless spring alloys

A distinctive feature of their use is the absence of residual deformation - under shock and static loads, the parts experience only elastic deformation. They must deform under loads within a given range, and upon completion of their action, restore their original dimensions and shape.

Technical requirements for spring-spring stainless steel:

• High strength to brittle fracture.
• Through hardenability.
• Resistance to stress relief.
• Good ductility and fluidity.
• High endurance and elasticity.

In fact, the material must have both high-strength and ductile properties, which are achieved by hardening, followed by tempering and the introduction of alloying elements: chromium, boron, vanadium, silicon, manganese.

Spring steels with a high chromium content and a high content of silicon, an alloying element with the help of which a high elastic limit is achieved, are widely used. AISI 321 has an alloy composition of up to 1% silicon, 17-19% chromium; AISI 304 – 18-20% chromium, less than 0.75% silicon, up to 2% manganese.

Manganese and silicon are added to steel in small quantities. Increasing the endurance of spring metal products is achieved by shot blasting the surface.

Application area

Alloy metals are used for critical parts with a large cross-section of turns. Spring stainless steel is used for the production of parts, elements of instrument making and mechanical engineering: washers; clamps; torsion bars; bending, torsion, extension, compression springs.

For the manufacture of springs, stainless steel grades AISI 304, AISI 321, etc. are used. The strings of musical instruments are also made from it. Order stainless steel products for the production of high-quality wire at the warehouse of the Globus-Steel company.

Source: https://www.globus-stal.ru/articles/osobennosti-nerzhaveyushchey-pruzhinnoy-stali/

Spring steels

Spring steels are special steels that are intended for the production of various elastic elements, in particular springs and leaf springs.

Spring steels

This type of material belongs to high and medium alloy steels. The main difference between spring steel and other types is the significantly increased yield strength of this material. In other words, we can say that this type has a high degree of elasticity, that is, it returns to its original state and shape after the load is removed.

This parametric property is determined by the area of ​​application of springs and springs. In normal operation, they are constantly subjected to compression/tension or elastic deformation and must perform their functions even after a long cycle of applying and removing deformation.

Also, this material must have good ductility and high resistance to brittle fracture.

The main alloying elements are silicon, manganese, tungsten and nickel. These additives increase resistance to plastic and elastic deformation by refining the alloy grain. Wire can also be considered a finished product, which is subsequently used in the manufacture of twisted and assembled springs.

Properties of spring steel

The main characteristics of this type of steel are high resistance to elastic deformation and low residual elongation coefficient. This is due to the inadmissibility of increasing or decreasing the structural size of the spring.

Steel spring

Good structural and operational properties are achieved by drawing a pre-patented wire at low temperatures, while tightly tightening the material.

The patenting process is carried out in the interval between two hoods, the steel is heated above the temperature point of austenite formation and then cooled in a bath of molten lead, while the austenite transforms into thin-plate sorbitol and its mechanical strength increases.

To achieve the same physical and chemical properties over the entire cross-section of the material, spring steel must undergo a calcination process using a through method, this will ensure a homogeneous structure throughout the entire cross-section. This method is especially important for the manufacture of springs of large diameter, when uneven properties of the starting material can lead to destruction of the finished product.

Like any other material, spring steel is characterized by the presence of carbon in its composition. In this case, its content can vary between 0.50-0.80% by weight of the alloy. Additionally, the following alloying additives are used:

• silicon – up to 2.5%;
• manganese – up to 1.3%;
• tungsten – up to 1.3%;
• nickel – up to 1.7%.

Microstructure of spring steel

It is worth noting that chromium and manganese, when alloyed together, increase the resistance of steel to low plastic deformations. Nickel and tungsten form a thin and uniform structure of the carbide fraction, which prevents dislocation.

Spring steel is very critical to deformations of the outer layer of the material, since these stresses are concentrators of possible defects in the finished product.

Hardening of this type is carried out at temperatures of 850–880 °C, but after such heat treatment the steel exhibits weak elastic properties due to the formation of martensite; to increase this type of properties, it is tempered at temperatures of the order of 420–510 °C, which promotes the formation of troostite and increased elastic deformation alloy to a tensile strength of 1200-1900 MPa and a yield strength of 1100-1200 MPa. At the same time, carrying out hardening isothermally - at a constant temperature - has a positive effect on the plasticity and viscosity of the material.

Steels of this type have good anti-corrosion properties due to the presence of alloying additives such as chromium and molybdenum in the alloy. This has a positive effect on the service life and prevents the formation of cracks during operation.

It is also worth noting several main disadvantages of spring steel:

• poor weldability - this is due to the destruction of the outer layer of the material and local overheating of the part;
• difficulty of cutting - some difficulties arise when trying to cut this type of steel, this is directly related to the high resistance to deformation.

Classification of spring steels

To begin with, let’s look at the marking of this type of material, most often it looks like “50A2BVG”, where: 50 is the carbon content in fractions of a percent; A2 is the alloying element No. 1 and its content in percent;

B, C, D – alloying elements No. 2,3,4, etc.

Important! If there is no number after the designation of the alloying element, it means that its mass content does not exceed 1.5%; if the number is 2, the mass fraction is more than 1.5%, but less than 2.5%; if 3, the mass fraction is above 2.5%.

For example, 50KhGF steel is an alloy in which the carbon content is 0.50%, and the alloying components chromium, manganese and vanadium are less than 1.5%.

If the steel marking contains only a number, for example, St. 50, St. 65, etc., this means that it refers to carbon steels, and if the name contains at least 2 elements, such spring steel refers to alloy steels.

Let's consider the main classifications of this type:

1. By processing method:
   1. Forged and hot rolled.
   2. Calibrated.
   3. With special treatment of external surfaces.
   4. Hot rolled round with ground surface.
2. According to the chemical composition of steel:
   1. High quality.
   2. High quality.

The grade of spring steel makes it possible to determine its structural and physical and chemical properties, determine the scope of use and machining capabilities.

Application area of ​​spring steel

Based on the name, we can conclude that this type is intended for use in areas associated with large elastic deformations, stretching, and torsion.
Such steel is used to manufacture all kinds of springs for various technological equipment, strips of steel for springs, calipers, etc. Main areas of use:

• production of springs for cars and heavy equipment;
• production of springs for technological equipment, this applies to compression and tension springs;
• springs are flat, cylindrical, complex from rods of various sections, etc.
• elastic elements of heavy machinery, machine tools;
• springs for tractor and locomotive equipment;
• land equipment knives;
• blocking and braking devices;
• bearing races.

car spring

Let's look at a summary table of the most common grades of spring steels, indicating their markings and areas of application:

Marking	Main alloying components	Operational Features
50ХГ	Chromium, manganese	Car springs, railway springs
50ХСА	Chromium, silicon, nitrogen	Elastic elements of watch technology
55ХГР	Chromium, manganese, boron	Stamping of spring plates
60С2	Silicon	Torsional shafts, collets, spring washers
60G	Manganese	Spring rings, tires, brake shoes
65	—	Parts operating under high friction conditions
65S2VA	Silicon, tungsten, nitrogen	Leaf springs operating under high dynamic loads
70G2	Manganese	Knives for earthmoving machines
70С3А	Silicon, nitrogen	Heavily loaded mechanism springs
85	—	High strength friction discs

As can be seen from the table, the size and quantity of alloying additives are directly responsible for the wear resistance and mechanical strength of parts. It can be seen that with an increase in carbon content from 0.5% to 0.85%, the strength and elasticity of the material increases, chromium prevents the formation of rust, tungsten increases the hardness and red-hardness of steel, and manganese increases impact resistance.

Source: https://stankiexpert.ru/spravochnik/materialovedenie/ressorno-prujinniye-stali.html

How to make a knife from a spring

Experts in the knife craft manage to make blades out of anything. There was a piece of iron lying around in the barn - a couple of days of work, the blade was ready. Not being surprised by such people is simply nonsense. Invariably, individual products turn out to be works of art. And the knife made from springs looks unique in its own way. Let us sanctify the theme of the painstaking work of the master.

Homemade knife made from springs.

Features of a knife made from a spring

A characteristic feature of spring steel grades is the ability of the product to take its original shape after deformation - twisting or bending. Parts that take part in mechanisms with specific loads must have complex properties.

The alloy is actively used by professional knife makers and makes it possible to obtain a blade with unique properties. The highest strength plus the ductility and wear resistance of the material allows craftsmen to produce blades worthy of attention.

Spring steel is an inexpensive option for carbon steel. The chemical composition gives it elasticity and toughness. Quenching the alloy gives a hardness of 60-62 Rockwell units. Modern craftsmen undertake to make products from 65G steel, considering it the most suitable.

Properties of spring steel

There are many opinions about the springs of cars originally from the USSR. Supposedly they are a really good material for a blade. It is useless to argue; it is easier to find out what grade of steel the product is made of. Experienced metallurgists claim that spring steel includes many grades:

• springs for railway cars and springs for cars are made from: 50HG and 50HGA, 50HGFA;
• mechanical engineering, tractor manufacturing uses 55С2;
• heavy-duty spring mechanisms and springs are made from 55S2GF;
• parts least susceptible to shock loads use 65G.

The list is quite long and there is no point in covering it all. But it is worth noting the approximate similarity of these steel grades both in chemical composition and physical properties.

The main guideline for creating such products is the ability to restore their original shape after various loads, i.e. - spring back. The slightest destruction during operation of the product is unacceptable. In accordance with GOST, excessive requirements are imposed on such alloys.

The use of spring steel for making a knife

Spring material 65G is used by amateur knife makers to make knives. Thanks to its unique characteristics, the metal finds its application in various fields.

Blades for the kitchen, hunting, tourism - all show excellent cutting qualities. If there is a special need, you can actually forge a sword or an ax. After hardening, the steel acquires good rigidity, which allows the product to be cut. Examples of using spring steel:

1. Kitchen knife. In difficult times for the country, after the collapse of the USSR, not all people could afford a good set of kitchen knives. I had to get out. Springs and plates made of 65G steel were easily accessible. In the kitchens of the post-Soviet space, homemade products were often found. The handle was made from improvised material: wood, simple epoxy, and electrical tape - which did not prevent the knives from remaining at their height.

1. Tourist knife. The disadvantage of spring metal is that it is susceptible to corrosion and requires constant care after use. The knife is suitable for use in hiking conditions. An important point is hardening. If it is weak, the blade will quickly become dull on the tin can. You should know the hardness of the knife.
2. Army. Tactical or, nowadays, military knives do their job well. Serrated sharpening will increase the scope of use of the blade. Withstands piercing blows without problems. In everyday conditions it will become a valuable assistant for a fighter or a “survivalist”.
3. Axe, machete or sword. Alloy 65G and analogs allow you to make truly formidable weapons. The thickness of the product certainly plays a significant role. When producing such a masterpiece, you need to stock up on springs from a truck, or get a long plate.

With proper processing of the metal, we are guaranteed to get an excellent blade. Little experience with the manufacture of steel products, nonsense. Further, in the article we will provide a detailed description of the manufacture of knives from springs using various methods.

How to make a knife from a spring using forging

Working with metal is a delicate matter. Forging a product requires certain skills. There is nothing wrong with ruining one piece. The experience gained will be useful the next time you try. We will work with a spring, approximately steel grade 65G; the color of the workpiece when heated will help determine the exact alloy.

Professionals consider the forging method to be more practical. When a metal is repeatedly heated and cooled, processes occur at the molecular level. Compaction of the metal and changes in structure will affect the quality of the product.

Tools and materials

Work should be carried out outdoors or in a spacious garage with an exhaust hood. It’s worth taking care of your health, finding a mask and heat-resistant gloves. The forging kit looks like this:

• steel blank from a spring;
• forge or oven;
• large hammer 4-5 kg, small hammer 1-1.5 kg;
• anvil, forceps;
• grinding machine;
• welding machine, angle grinder.

A simple fire with air supply is quite suitable as a heating element. Throw in coal and there will be no heating difficulties.

Blade forging

All spring products are hardened at the plant. The steel must be annealed. The process is carried out by gradually heating the workpiece to a temperature of 800-900 ° C and leaving it to cool in air. The part is ready for use:

1. After annealing, the metal becomes more pliable to any manipulation. It’s easier to weld the rod; for convenience in further work, you won’t need tongs.
2. If the workpiece has a curved shape, it is worth heating it red-hot and straightening it with a small hammer. Be sure to monitor the temperature. Do not work with cold metal.
3. The forging temperature is 1000-1100 °C, without having a thermometer, you should determine it by eye (dark yellow) or with a magnet - the workpiece will stop sticking to it. The color and thermometer indicate that the steel is actually grade 65G.
4. We hammer the product with a large hammer and stretch it to length. Springs generally have a thickness of 5-6 mm; stretching should be continued until a thickness of 3-4 mm.
5. It is better to forge the slopes and the nose to the tip of the blade right away, in the future there will be less hassle on the grinding machine.

Having acquired the appearance of a blade, the product should be cooled in air, and the rod should be cut off with a grinder. Having more specifically marked the slopes and the shank, continue processing on the grinding machine. We will definitely describe the processes of making the handle and hardening the blade below.

How to sharpen a knife from a spring with your own hands

Cutting or forging is the personal choice of the knife maker. To bend the workpiece you need a furnace. It is better to take a thinner spring, otherwise there will be a lot of fuss with the thickness of the workpiece: you will get tired of removing it and will erase several circles. The required tool is slightly different from the forging version

• Angle grinder, grinding machine, wheels for them with different grains;
• furnace and spring preparation;
• files, hammer, anvil;
• marker, paper;
• sandpaper with different grains.

A turned knife from a spring.

You won’t have to work with a hammer, it’s more hassle with a grinder and a grinder. When starting work, protect your eyes and hands.

The process of making a knife from a spring

If you follow the instructions, the blade will come out no worse than a forged one. It is important not to overheat the workpiece and carry out the hardening accurately:

1. After completing the annealing process and straightening the workpiece, it is necessary to make a template for the future blade. The imagination of a knifemaker and the Internet will allow you to create a unique blade template.
2. The sketch must be completed with a margin of a couple of millimeters, in case the metal overheats. Circle it with a marker on the workpiece and begin the labor-intensive process of cutting.
3. The thick spring will have to be removed to 3-4 mm; an angle grinder or grinder will help to do this. Having equipped the grinder with a cutting wheel and securing the workpiece in a vice, we cut out the future blade along the contour. Monitor the color of the metal and do not allow it to change. Changes color - overheating. Water more.
4. Once the cutting process is complete, files will help remove burrs. Mark the slopes symmetrically and remove them with a grinder.

Having received a product close to the blade, you should not sharpen it immediately. Don't forget to process the shank. The knife is almost ready, there are a few nuances left.

Blade hardening

There are enough hardening options. When working with 65G steel and analogues, professionals recommend producing it in oil. But there is an opinion that it is preferable to carry out the process in the air. Let's focus on the oil method.

After heating the oven to 900 °C, below the forging mark, carefully place the blade and monitor the heating. Having reached the orange color of the part, take it out with pliers and lower it into the oil for 3 seconds. Take it out and wait for it to cool completely. Place it in the oven again, heat it and add oil. We increase the exposure time by 1 second.

You need to do the procedure 3 times with a gradual increase in the immersion time by 1 second. The blade will acquire high hardness and will not lose its plastic qualities. Our resource contains a more detailed procedure for hardening knives at home.

An important point is the release of the blade. Tempering is carried out at a temperature of 200 to 300 °C. The process can actually be carried out in the oven of a gas stove. Having heated the workpiece to the required level, you should leave it for 2-3 hours without reducing the thermometer readings.

Making the handle

There are 2 types of handles: overhead and mounted. For blades with high hardness, option 1 is used.

Drawing of knife handle elements.

The method is simple, you will need:

• block of wood;
• drill, drill bits;
• epoxy glue, pins;
• sandpaper;
• grinding machine.

Wood can be replaced with: plastic, plexiglass, etc. The material is suitable for various applications. Having cut out the appropriate size pads, we drill holes in the shank. The same is true for handle blanks.

Having brought the pads to an ideal plane with sandpaper, glue them to the shank and insert the pins - they can be riveted. We secure the structure with clamps and leave it to dry for 24 hours. Using a grinding machine, we bring the handle to the required size.

The wood must be impregnated with oils or anti-aging wood products. Our resource has a detailed article on installing the handle.

Knife sharpening

The hardness of the resulting knife will be 60-62 units on the Rockwell scale. After making sure that the slopes are symmetrical, you can start sharpening. The process begins with a rough, coarse-grain whetstone. Professionals advise using diamond stones to sharpen knives.

Movements are carried out along the bar until a burr appears. We move on to a stone with a slightly smaller grain, moving the blade progressively. The process does not require fast and sudden movements. When sharpening, you must maintain a constant angle. It depends on the future use of the knife. The optimal angle is called the option of 20-25 degrees.

To remove a burr, you need to work on the finest grain. Don't forget to moisten the block with water. Sharpening a knife will require considerable effort. Spring steel, after hardening, is very hard.

Taking into account the operating conditions, having sharpened the blade once, the blade will not become dull soon. A properly sharpened product is capable of cutting tin sheets without losing its qualities.

Source: https://VashNozh.ru/izgotovlenie/nozh-iz-ressory

Spring steels: characteristics, properties, grades, GOST. Spring steel products

It’s worth starting with the fact that any spring, leaf spring and other similar elements are operated under conditions of severe and constant elastic deformation. In addition, most parts are also subjected to cyclic loads. It is for these reasons that high demands are placed on spring steel in terms of elasticity, fluidity, endurance, ductility, and it is also important to have the necessary resistance to brittle fracture.

Compound

The composition of steel, which is suitable for the production of springs and leaf springs, contains from 0.5% to 0.75% carbon. Additional requirements for alloying elements during production are as follows:

• silicon content in spring steel up to 2.8%;
• manganese content up to 1.2%;
• chromium alloying reaches 1.2%;
• vanadium content up to 0.25%;
• tungsten alloying up to 1.2%;
• Nickel content up to 1.7%.

It is also important to add here that during the production of steel, a process of grain refinement is carried out, which contributes to an increase in the metal’s resistance to small plastic deformations. This, in turn, increases the relaxation resistance of the spring steel product.

Application

Products made from steel grades such as 55S2, 60S2A, 70S3A have found quite wide application in vehicles. But here you need to know that this material is susceptible to defects such as decarburization or graphitization. These disadvantages are dangerous because they greatly reduce the elasticity characteristics and strength of the material. In order to avoid these defects and their negative impact on spring steel, the elements mentioned above are added to it.

In contrast to the silicon variety of the alloy, the 50HFA grade has the best performance. This type of material has become most used for the manufacture of automobile springs. This type of steel is also very often used for the production of spring valves, as it is not susceptible to decarburization. But here it is worth adding that it has low hardenability.

Spring operation

It is important to understand here that the operation of any spring, leaf spring or any other part made of spring steel is characterized only by the fact that only the elastic properties of the material are used. The total value of their elasticity is determined by the design features. The decisive indicator here will be the number of turns, their diameter, as well as the length of the product itself. Another important point to note is plastic deformation.

This is most often not allowed in springs, and therefore the material used to produce springs is not required to have high impact strength or ductility. The main requirement is the elasticity parameter. The upper limit of this characteristic should be quite large.

In order to achieve the required parameter, the steel is hardened under high temperatures, and then the material is tempered at a temperature of 300-400 degrees Celsius.

The main property of spring steel is fluidity (elasticity). The maximum value of this parameter is achieved only at the temperatures indicated above. However, if the material is tempered at such degrees, then the tempering brittleness of the final product will be of the first order. As mentioned earlier, impact strength is not of fundamental importance.

https://www.youtube.com/watch?v=PDpFBJpLokE

Another property of steel concerns its composition. It is expressed in the fact that the carbon content in it is higher than in other alloys. Although, when compared with tool steel, it is still less.

For the usual alloying process, manganese and silicon are used. For more critical springs or leaf springs, chromium and vanadium are used as additives. These two elements give them increased elasticity. It can be added that to achieve the best performance properties, steel is often quenched in oil or water.

Types and grades of steel

Spring steel grades are divided into many different groups. There are general purpose materials. These include brands 65, 70, 75, U9A. Springs for machines with small cross-sections are made from this product. The special properties of these parts include their reduced relaxation resistance.

Silicon steels of grades 55С2, 60С, 60С2 are used to create elements such as springs and springs used in the automotive, automotive and tractor industries, as well as in the railway industry. It is important to add here that these elements are prone to decarbonization. This steel does not have any special properties.

Another type of steel is complex alloy. This product is produced under the brands 50HFA and 60S2HFA. This material is used when it is necessary to create springs or springs for important parts. The temperature resistance of this material is up to +300 degrees Celsius.

Special purpose steels can also be distinguished. These include martensitic class products 30Х13, 40Х13. They are used to produce ordinary springs or leaf springs, but have special properties. The characteristics of spring steel of this grade are that it has increased resistance to corrosion, increased heat resistance (up to 550 degrees Celsius), as well as pronounced magnetic properties.

Requirements according to GOST

For spring steels, as well as for other very diverse products, GOST was adopted. He sets all the rules regarding the material. For example, the following technical requirements are described there.

• The mass fraction of a substance such as copper should not exceed 0.2%. And the residual amount of nickel should not be higher than 0.25%.
• For a steel grade such as 60S2G, there is a separate requirement, which states that the total mass fraction of sulfur and phosphorus should not be higher than 0.06%.
• A steel grade such as 51HFA according to GOST is intended only for the production of spring wire.
• GOST spring steel also prescribes that, by individual order of the consumer, the mass fraction of manganese contained in the steel can be reduced, despite the requirements that are indicated in the table available in the same document. This is provided that the alloy has not been alloyed with chromium and nickel.

Corrosion resistant steel

One of the special-purpose steel grades is distinguished by its increased resistance to corrosion. In order to maximize the resistance of the material to the process that destroys it, both chromium and nickel are added to it in amounts from 13 to 27% and from 9 to 12%, respectively. In other words, these products belong to the group of high-alloy steels.

The main austenite-forming element in such a product is nickel. While manganese, for example, has a weaker effect on the formation of austenite, the effect of its use is almost two times lower. If it is necessary to further expand the austenitic region, substances such as carbon or nitrogen can be used.

Source: https://FB.ru/article/345052/prujinnyie-stali-harakteristiki-svoystva-marki-gost-izdeliya-iz-prujinnoy-stali