How to find out what metal

How to determine what we have in front of us: brass or copper, their main differences

Anyone who searches for and sells non-ferrous metal sometimes has doubts about the type of scrap and, accordingly, its true value upon delivery.

Copper is a non-ferrous metal, and brass is an alloy that is typically 70% copper, so it often resembles it.

A mistake can be quite costly. For copper at collection points they give 285-300 rubles, for brass - about 150 . There are many ways to find out what kind of metal we see - copper or brass, and we will tell you how to distinguish them from each other in this article.

What is copper and brass

Copper is a non-ferrous metal. Its color is reddish-pink, it is pliable when working, soft and malleable. It has high thermal and electrical conductivity, so copper is often used to produce:

parts of electrical appliances;
cables;
radiators.

Copper is not hardened because it becomes hard even after cold forging. It tends to become covered with patina - a green coating that occurs when the ambient humidity is high.

To increase strength, improve a number of other indicators and reduce the cost of the material, impurities are added and an alloy is obtained.

One such alloy is brass .

In the classic version it contains a third of zinc.

Brass is golden yellow, stronger and harder. It does not oxidize so intensively , and is not so plastic.

Sometimes, depending on the purpose of the alloy, they add:

tin;
silicon;
lead;
manganese.

Similarities and differences

Brass alloy consists mostly of copper, so it is natural that they are similar not only visually, but also in some properties. The more copper in the alloy, the more similar their colors will be. This is where the exact coincidences end.

Visually, less than 80% copper are easily distinguished . They are slightly similar to gold, as they have a pronounced yellow tint. The more zinc, the lighter the shade.

Because of this, brass is even used to counterfeit or imitate gold . Copper has a main shade of reddish, which often has a pink tint.

With a strong decrease in temperature, brass does not lose its relatively limited ductility and does not become brittle . Conducts electricity and heat worse.

They differ in such a way as hardness .

Copper is softer and more ductile , while brass, on the contrary, is hard and it is difficult to give it any shape without annealing.

The shavings are also different: for brass they are needle- shaped , for copper they are twisted into a spiral .

Let's look at the properties that brass and copper have and whether they have any differences:

Copper	Brass
Plastic, soft	Solid
Reddish-brown-pink tint	Golden tone
Lower sound on impact	Alt
Heavy	Easier
The shavings are twisted into a spiral	Needle shavings

Most often you can distinguish by:

mind;
weight;
degree of hardness

without the use of any tools or equipment.

But there are situations when, for accuracy, it is necessary to use :

reagents,
tools,
devices.

Before assessing the scrap that you are going to take to the collection point, you need to clean it of dirt, otherwise you won’t be able to accurately determine it by eye.

Both metals, although to varying degrees, can develop a patina .

Therefore, do not forget to clean the scrap well.

If an object has been in the open air or in water for a long time, the patina layer is difficult to remove.

Sometimes it will be justified to purchase a special cleaning product .

It is advisable to inspect the scrap under a powerful white light.

This implies that one can view either under the sun on a fine day or under a bright fluorescent lamp . Incandescent lamp is not suitable.

Pure copper will have a reddish-brown tint, sometimes with a pink tint. Keep in mind that brass can be red or orange. This type is commonly used for decorations and water pipes.

If the material has an orange, yellow or golden tint, you can be almost sure that it is brass.

Source: https://rcycle.net/metally/cvetnye/kak-opredelit-latun-ili-med-ih-osnovnye-otlichiya

How to determine the category of scrap metal?

Payment for an unsorted batch of scrap metal is usually set by the receiver at the level of the cheapest grade. Naturally, the maximum benefit from the delivery of recycled ferrous metal can be obtained by first preparing the scrap according to the established categories. The main types of ferrous metal waste are determined by GOST 2787-75 and are slightly modified at collection points, for example, for railway or automobile scrap.

Principles for constructing categories

The classification of recycled ferrous metals is carried out in accordance with GOST, based on the following characteristics of scrap metal: carbon content, quality grade of recyclable materials and the presence of alloying additives, their type, concentration. Since the most popular scrap metal is unalloyed iron, the category of waste is determined by two parameters: the type of iron and the quality (final form) of the scrap.

Based on carbon content, there are two classes: recycled steel (no more than 2.14%) and cast iron scrap. The quality classification is more diverse and includes 28 types. A characteristic feature of the quality distribution of ferrous metal scrap is its orderliness: the first 16 classes are reserved for steel waste.

The scrap metal category designation contains three components. The first component is the number of the type (quality) of recyclable materials, according to GOST. The following symbol corresponds to the presence of alloying impurities: A – carbon metals without additives, B – alloyed. The third parameter, auxiliary (not established by GOST), indicates a specific type of scrap metal, for example railway - railway.

This classification makes it easy to determine the type of metal:

1A – 16A – steel waste;

14A – 24A – cast iron scrap.

The remaining four classes are reserved for low-grade scrap metal and are not particularly popular.

Qualitative characteristics of waste

As stated earlier, high demand is exclusively for carbon scrap, without alloying additives. This is due to GOST requirements for the acceptance of alloyed scrap metal, which prohibit the presence in the batch of fragments with a different chemical composition (grade).

The determining element of the cost of ferrous metal scrap is its quality, which is classified into the following types:

compressed bags made of lightweight structures;

cast iron and steel shavings in bulk or briquetted form;

unsorted recyclables.

An additional characteristic of recycled cast iron is its phosphorus content. Scrap metal with a high concentration of this element is classified into separate categories. Considering the significant (double) difference in cost, shavings and wire are less popular and are not accepted by all points, leaving the palm to lump recyclables.

Most Common Categories of Ferrous Recycled Metal

Among steel scrap, categories are very popular, which, in principle, you need to distinguish between before handing over scrap metal:

3A – dimensional recyclables, with size restrictions of 800 (some collection points allow 1500) x 500 x 500 mm. The category includes pipes with a diameter of up to 150 mm (accepted in one piece). If the size is exceeded, the pipe must be opened at the seam or flattened.

Metal cut to size - a typical representative of category 3A

5A - oversized steel scrap, wall thickness must exceed 4 mm, solid pipes with a diameter of over 150 mm are allowed.

In the photo, scrap category 5A - any oversized steel scrap

12A – waste steel up to 4 mm thick.

The profiled sheet will be classified as category 12A - tin

Recycled steel has additional subcategories established at collection points (not included in GOST). For example, 3AP – railway scrap, including rails. Category 3AN concentrates large scissor waste.

Oversized rail recyclables, including wheel sets, are classified as grade 5AP - by the way, one of the most expensive types of scrap metal. Scrap of motor vehicles, construction and agricultural equipment contains category 12AN. The equipment must be deregistered by the traffic police.

This also includes broken household appliances: washing machines, refrigerators, etc.

The most common types of cast iron scrap metal are:

17A – cast iron scrap with size restrictions of 1500x500x500 mm

20A – oversized cast iron waste.

Oversized cast iron scrap

19A/22A – recycled cast iron with a high phosphorus content, usually heating batteries, plumbing products.

All scrap metal must be free of non-metallic inclusions, free of flammable substances, and not rusty.

Source: http://xlom.ru/vidy-metalloloma/kak-opredelit-kategoriyu-metalloloma/

How to identify non-ferrous metal?

Today, many owners of private houses are trying to make the most of their own capabilities. We are talking about organizing a workshop. The presence of even a primitive lathe will allow you to produce a wide variety of parts for a wide variety of purposes. In any case, repairing garden equipment or even your own car will become much easier.

Meanwhile, savings can be achieved by purchasing metal raw materials on the most favorable terms. Today on the Internet you can find the most attractive prices for aluminum rods. Many people purchase metal for further use at scrap metal sites. Here the question arises - how to distinguish ferrous metal from non-ferrous metal?

The actual difference between ferrous and non-ferrous metals

Surveys show that the average person cannot answer this question. The essence of the answer lies in the composition of the metals.

Ferrous metals contain an admixture of iron. Therefore, ferrous metal can be determined using an ordinary magnet. If it sticks to a metal part or workpiece, we can say with confidence that it is made of ferrous metal.

However, there are exceptions to any rule. Nickel also attracts a magnet, although it is considered exclusively non-ferrous metals. Additionally, the magnet rule does not apply to some metal alloys.

These include stainless steel.

Non-ferrous metals that are not magnetic

These can safely be attributed to:

aluminum;
copper;
brass;
bronze

However, there is an easier way to identify ferrous metal. If you purchase metal at a dealer (reception point), it is very likely that it is located in the open air.

We are talking about the fact that the metal is affected by precipitation. This means that it is in no way protected from corrosion. Consequently, ferrous metals immediately begin to become covered with rust.

Source: http://euroelectrica.ru/kak-opredelit-tsvetnoy-metall/

In what ways can you determine which metal? Iron is colorless, magnetic and rusts. Aluminum is whitish in color, not magnetic, oxidizes with a white coating. Copper has a reddish tint; when oxidized, it darkens and becomes covered with a green coating. Do not magnetize. When burning, the flame is greenish. Bronze is yellowish in color, almost does not oxidize, and does not rot. Stainless steel - no color (or grayish), not magnetic or maybe. Magnesium is a silvery-white hue, not magnetic, the smell is a little sweet, when burning the flame is bright white (flammable). Titanium is a grayish tint, not magnetic.. You can somehow determine it by the color of the flame when burning. But which color belongs to whom? Steel is somehow determined on sandpaper by the shape and color of the sparks. How can we determine that this is an alloy and not a pure (relatively) material? Who has information on the definition - please share. Pure metals are not used in mechanical engineering, are they? If only silver, gold or palladium is used in the contact coating, and all construction materials are alloys. Even copper in conductors. Boiling steels can be identified by sparks on a circle - rare long, orange lines. High carbon ones will give a rich bunch of light sparks with *stars* at the end. The more carbon there is in the steel, the lighter the color of the sparks, and the more *stars* there are. Tool steels will produce short, broken beams of sparks with *stars*. Payment for an unsorted batch of scrap metal is usually set by the receiver at the level of the cheapest grade. Naturally, the maximum benefit from the delivery of recycled ferrous metal can be obtained by first preparing the scrap according to the established categories. The main types of ferrous metal waste are determined by GOST 2787-75 and are slightly modified at collection points, for example, for railway or automobile scrap.

How to determine what metal at home - Metallover's Handbook

Silver is a mysterious metal. Despite its lower financial value, unlike gold, the metal has always been endowed with unusual and even magical properties.

It was used not only as a raw material in jewelry: it was previously believed that eating and drinking from silver utensils was a way to improve your health. In addition, monarchs of different countries used silver drinking cups for safety purposes.

It was believed that silver reacted with poisons, which could immediately change the color of the drink or cup.

Silver

In the modern world, pure silver balls are used to purify water. Silver membranes are also used in the production of various drinks, as one of the ways to clean them from harmful impurities.

Legends

Naturally, there are many legends and rumors surrounding silver. One of the most popular was the use of silver weapons in the fight against evil spirits. Various folk epics mentioned silver as a special magical device that allowed one to protect oneself from evil spirits.

Silver

Silver was the raw material in the minting of ancient coins. The main biblical story about the betrayal of Judas also talks about the silver (pieces of silver) that he received from the high priests for betraying Christ. There is also a branch from here. For example, one of the deadly sins that characterizes greed and stinginess is the love of money. The root of the word silver is also used for a reason. Before the “gold rush” period, silver was the dominant unit of account in the world.

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It is also believed that silver jewelry can help cope with many ailments. Among other things, it is believed that silver helps overcome a hypertensive crisis, normalizes blood circulation, improves the functioning of blood vessels, which stabilizes blood pressure. Also, wearing silver in the form of bracelets can purify the blood. In addition, unlike gold, silver does not cause allergic reactions at all, and is even recommended for wearing by people with sensitive skin.

Definition

How can you determine the authenticity of a metal? There are many ways. If you wish, you can contact any pawnshop or bank where there is a specialist.

There, thanks to special manipulations, the authenticity of the silver, as well as its fineness, is established. By the way, it should be noted that the silver sample is an indicator of the purity of the metal. The most common sterling silver in the jewelry industry is 925 sterling silver.

This metal contains virtually no impurities. It has a uniform color and, when properly processed, a bright shine.

However, many people often wonder whether it is possible to authenticate metal at home? What needs to be done to determine whether an item is silver and what is its purity? After all, with the naked eye it is very difficult to distinguish pure silver from well-processed simple metals. Therefore, let’s try to figure out how to analyze metal at home, without having a whole laboratory and chemical reagents at hand.

Method 1

The easiest way to determine whether a piece of jewelry is silver is to hold it in your hands. If you squeeze a ring or bracelet into a fist and hold it for a few minutes, you can identify the following features:

the metal left traces - the composition contains zinc, which is not very useful;
the metal has darkened - perhaps this is an oxidation reaction that should not happen with silver.

Method 2

Metal cleaning. Silver is easy to clean. To do this, you can use ordinary toothpaste or powder, as well as ammonia. If the darkened areas are not cleaned off, it means that there is another metal in front of your eyes that has nothing to do with silver.

Method 3

Heat check. Silver is a good heat-conducting material. If you hold it in your hands, it will heat up quickly. The same thing will happen if you put it in warm water. The metal will very soon have the temperature of water. You don't need to wait long for this, just a few seconds are enough. Other metals take longer to heat up.

Method 4

Magnet. Silver is not magnetic, so if you apply it to a magnet, nothing will happen. Most other metals will be attracted to a magnet. Naturally, its actions do not apply to aluminum, but it is not so difficult to check. Aluminum varies in color and is very fragile.

Method 5

To bend. If you try to carefully bend the product in a certain place, it will work with silver, but it will not work, for example, with brass. The latter does not bend, but springs. Thus, it is easy to determine the authenticity of the metal. But bending is not always convenient, as this can damage the appearance of the product.

Method 6

Silver has a specific smell, unlike other metals. However, this test method is quite complicated without knowing the initial smell. And there are a lot of flavors now.

Method 7

Sulfuric ointment. This substance is commercially available and is very inexpensive. If you apply a small amount of sulfur ointment to an area of silver and leave it for a couple of hours, the silver will turn black. More precisely, the treated area will change color after the ointment is removed with a napkin. Most other metals do not change color even when exposed to this substance.

Method 8

Iodine. If it is not possible to get sulfur ointment, you can use iodine. The area where the substance is applied will definitely and quickly turn black. However, iodine is quite difficult to wash off, which must be taken into account before the experiment.

Method 9

Chalk. If you rub a piece of regular chalk on silver, the chalk will darken. This is also one of the easiest ways to check the authenticity of metal. Silver reacts quite well with the components of chalk, so you won’t have to wait long. The procedure is absolutely safe for silver.

In fact, identifying silver at home is an important point, since modern craftsmen often offer processed brass under the guise of silver. Naturally, it will not provide any qualities of this metal, and it will soon darken and is unlikely to be cleaned to its original shine.

Source: https://ssk2121.com/kak-opredelit-kakoy-metall-v-domashnih-usloviyah/

How to identify metal: types of tests, use of chemistry

Probably everyone had to hold in their hands a piece of jewelry or another object, obviously metal.

But how can you determine what metal is used in production? It could be a precious material or a counterfeit, or even a trinket with no claims to value. Expertise from specialists will give you the exact answer, but it is not free.

But there are methods for approximately determining the type of metal at home. They were used a long time ago, but they have not lost their relevance in our time.

Magnet check

Bringing a magnet close to the item being tested is a good way to perform initial testing. By the reaction of the magnet you can determine which group the metal belongs to:

Ferromagnets. The magnet is clearly attracted to the object, which means that the product may contain iron, steel or nickel.
Paramagnetic materials. The interaction with the magnet is very weak. This group includes aluminum and chrome. Precious metals that are paramagnetic are platinum, palladium and silver.
Diamagnets. In general, they do not react to magnets. Copper and zinc have these properties. Precious metals - gold.

Magnet check

Of course, such a check will not allow us to accurately determine the material from which the item is made. After all, a non-magnetic metal may not be in its pure form, but in the form of an alloy with a ferromagnet. But it can confirm or refute the assumption. For example, if it is checked whether it is gold or not, but the item is clearly magnetic, then it can be argued that it is a fake.

When checking jewelry, you should take into account that, in addition to precious metals, they may contain clasps, built-in springs, made of another material. You need to check the metal itself.

Heat check

You can also determine the group of a metal by how it conducts heat. It is known that the thermal conductivity of silver is very high. It is almost five times higher than that of iron or platinum. Slightly worse for gold, copper and aluminum. Platinum transfers heat even weaker than iron.

If you immerse the metal in hot water for 15–20 seconds, then based on its temperature, determined by touch, you can draw some conclusions.

Gold and silver objects will become as hot as the water in which they were dipped.
During this time, platinum and items containing iron will become warm, but not hot.

In this way it is easy to distinguish platinum from silver. But it’s not possible to compare silver or aluminum alloy.

Iodine test

You can check the authenticity of the metal using an iodine solution purchased at a pharmacy. A drop of iodine is applied to the surface and left for several seconds. Iodine will not harm noble metals - gold, platinum, silver. If the color of a drop of iodine does not change, and after removing it with a napkin, no traces or stains remain, this indicates the authenticity of the metal. If darkening is visible at the place of the drop, then this is a low-quality alloy or an outright fake.

Iodine testing of gold

Vinegar test

Household vinegar solution also does not affect precious metals. And it is dangerous for counterfeits. But, unlike the iodine test, acetic acid takes time. To wait for the result, you need to immerse the metal being tested in a container with vinegar for 15–30 minutes. The absence of traces of interaction between metal and vinegar is a sign of nobility.

If, in addition to metal, the product contains precious or semi-precious stones, then it is better not to check them this way; vinegar can ruin them. This is especially true for pearls.

Dental check

From novels and films we know that they used to test the authenticity of gold coins by biting them. What exactly can be installed in this “old-fashioned” way? Gold is a soft metal. Therefore, even with a weak bite, a dent from the teeth remains on it. Fake alloys do not have this property; you cannot take them with your teeth.

Such a test gives good results for high-quality products. The higher the pure gold content, the softer it is. Gold of 900 purity and higher is so soft that they try not to expose valuable items made from it to contact with other objects.

This is how you can compare platinum and silver. The latter does not have the softness of gold, but a strong bite may leave a small dent. It is impossible to leave marks with teeth on real platinum.

Application of chemicals

Testing with active chemical reagents should be left as a last resort. If handled improperly, they will damage even genuine precious metal. And they can be dangerous for the health of the inspector.

Ammonia

Pure gold does not react to ammonia. But practically no products intended for use are made from gold 900 and 999, only for collections. And on a precious metal of lesser purity, ammonia can leave an irremovable mark. Its solution in combination with other substances is used to clean gold items. Therefore, it is not worth identifying gold and silver items using ammonia.

https://www.youtube.com/watch?v=-zO_poAblmw

Platinum products are usually produced with a high purity. Therefore, you can check the authenticity of platinum with ammonia. This chemical will not leave a mark on her.

Nitric and hydrochloric acids

Separately, these acids do not affect high-grade gold and platinum. And if you mix their concentrated solutions in a ratio of 1:3, you get a mixture called aqua regia. It can even dissolve gold. Aqua regia does not “take on” platinum when it is cold. This precious metal will gradually dissolve in the heated mixture.

Oddly enough, royal vodka is not afraid of genuine silver. It reacts to it by forming silver chloride in the form of a thin film on the surface. The latter protects the product itself from destruction.

Density check

One of the reliable ways to determine the type of metal or alloy is to determine its density. For pure gold it is two times higher than for copper and almost three times higher than for iron. Platinum is even heavier than gold. Even an alloy of 585 gold is noticeably heavier than base metals.

Of course, to determine the exact density of a small product you will need pharmaceutical scales, volume calculations (Archimedes' law to help) and tabular data on the density of base metals. But to solve the question of what the alloy is mainly made of, gold or another metal, rough estimates are sufficient. If you have at hand an object made of obviously genuine metal of approximately equal volume, then you may not even need a scale. A weight difference of two to three times is not so difficult to catch.

Separately, each of the considered methods will not give an exact answer to the question of what metal the product is made of. But if several different tests show the same results, you can be confident in the correct determination. If not, then you will have to turn to professionals.

Source: https://DedAntikvar.com/interesnoe/sposoby-opredeleniya-metalla

How to identify stainless steel: methods and materials

Stainless steel is the name of a group of iron alloys that contain corrosion-resistant metals. Carbon, titanium, copper are used as additives, and the composition also includes from 12 to 25% chromium and nickel. Alloy steel alloys are not susceptible to corrosion and are resistant to moisture, aggressive environments, alkalis and acids.

Stainless steel is used to produce dishes, knives, elements of machine tools, cars and industrial equipment, especially in the chemical and oil industries. Such scrap is accepted at a high price, which depends on the composition. The most expensive alloys are those with a high nickel content (from 10%). To get maximum profit from scrap metal, it is important to know how to identify stainless steel?

Metals and alloys that are often confused

The silver alloy of iron and chromium is suitable for the production of kitchen utensils, medical instruments, bearings, cutting elements, etc. But these items are also made from the following materials:

nickel-plated brass (a white copper alloy with a zinc content of more than 25%);
cupronickel (silver-white metal made from an alloy of copper and nickel);
white copper (an alloy containing at least 25% nickel).

Polished aluminum, nichrome, nickel silver and other alloys used for the production of cookware, knives, and jewelry can easily be confused with alloy steel. Despite their similar composition and high nickel content, they are easily distinguished at a scrap metal collection point and will not be accepted at the desired price. There are several ways to determine whether aluminum or stainless steel has fallen into your hands: chemical, mechanical, etc.

Analysis using a magnet

In the laboratories of large collection points, a spectrometer is installed - an optical device for spectroscopic research. It is equipped with an interferometer to evaluate the intensity of spectral lines and measure wavelengths. The received data is processed by a computer, giving an accurate conclusion about the composition of the alloy.

If you need to identify stainless steel at home, use improvised but relatively reliable means. One of them is a magnet: it is generally accepted that stainless steel is not magnetic. However, this diagnostic method is not accurate enough, because martensitic and ferritic alloys have magnetic properties.

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Using a magnet, only austenitic and austenitic-ferritic alloys with a high content of chromium and nickel can be detected. They are used to produce dishes, plumbing and refrigeration equipment, containers for food liquids, etc. Contrary to popular belief, it is impossible to accurately determine stainless steel with a magnet, but you can roughly identify its type.

Defining food grade stainless steel

As stated above, a magnet helps to identify food grade stainless steel at home. Alloys with a low carbon content and a large amount of nickel in the composition do not react to contact with it. Stainless steel with a high carbon content (more than 0.9%) has magnetic properties and is prohibited for use in the food industry.

Also, to determine food grade stainless steel, various acids are used (citric, tartaric, acetic, etc.). Alloys for food applications contain more alloying additives, so their surface film is stronger and contains almost no iron.

For additional protection against corrosion, passivation is used - a method of treating the surface of a metal, as a result of which its activity is reduced and it does not enter into oxidative reactions.

Under the influence of these acids, stainless steel may become covered with a light patina, which indicates its non-food purpose.

Types and grades of non-magnetic steels

If the origin of the product is known, the reaction with a magnet can roughly determine the type of stainless steel. The following brands are not magnetic:

AISI 409 (analogue 08X13) - containers for cargo transportation, parts for the exhaust system of a car, etc. are made from this ferritic steel. (plasticity and lack of magnetic properties are due to the extremely low C content - less than 0.03%);
AISI 304 (analogous to 8-12X18H10) - household items are made from it, as well as utensils and equipment for the food and pharmaceutical industries;
12Х21НБТ (ЭИ8П) – austenitic-ferritic steel for use in medium-aggressive environments, from which containers and equipment for the chemical and pharmaceutical industries are produced.

Stainless steel grades AISI 402–420, which contain from 11 to 14% chromium and less than 0.07% carbon, are not magnetic.

Magnetic stainless steel

AISI 430 steel (analogous to 08X17, which contains 15% chromium) has magnetic properties. It is used to produce wire mesh, pipes for transporting petroleum products, and elements of gas and oil refining process plants. Steel grade AISI 630 contains up to 5% nickel and chromium, as well as a large number of additives: copper, titanium, molybdenum. It is used in instrument making and metallurgy.

Stainless steel can be identified even if it is magnetic. To do this, place a sample of the material in 2% vinegar or another aggressive medium for 1–2 days. Corrosion-resistant alloys will pass this test without visible changes, but metals that are susceptible to corrosion will darken.

Copper sulfate will also help determine magnetic stainless steel at home. First clean the metal surface with sandpaper, and then apply a few drops of a concentrated substance (rusting alloys are covered with a red film).

Spark test

Testing metal for spark color is a common method of sorting scrap metal, which is used even by specialists. The grade of stainless steel can be determined by the following factors:

the number of sparks and flashes, which is directly proportional to the volume of carbon in the alloy;
the color of the sparks, which indicates the composition of the metal (the lighter it is, the higher the likelihood that this is low-carbon steel);
the presence of shiny white sparks, which indicates a high titanium content in the composition.

To carry out the test, an angle grinder (grinder) is required. Start grinding the surface of the steel and observe the reaction. The color, length and shape of the sparks will help you accurately determine metal or stainless steel.

"Yellow flow" or "white fork"

There are many types of sparks: “fork”, “twig”, “arrow”, etc. You learn to distinguish them with experience, but even an untrained person will be able to distinguish a dense and short stream of flashes from the long and rare sparks characteristic of stainless steel. The presence of dark red sparks coming out from under the grinding wheel indicates a high content of nickel, tungsten carbide and cobalt.

If a medium-density stream appears during the grinding process, and the sparks are straw-yellow at the base and white at the end, you have stainless steel. A long stream of sparks, reaching 1.5 meters, indicates the presence of nitrogen in the composition. In this case, it is not difficult to determine the grade of stainless steel: nitrogen alloys are quite rare and there are only a few of them (Nitrobe 77, Sandvik™ 14C28N, Böhler N680, etc.).

What does the price depend on?

Low-carbon, corrosion-resistant alloys are used to produce a wide variety of products: blades, profiled sheets, roofing materials, medical supplies. Scrap stainless steel can be collected when dismantling an old fence, dismantling an old refrigerator, throwing away unnecessary kitchen utensils, etc. In this case, potential income will depend on the following factors:

type of steel (austenitic, ferritic, martensitic, etc.);
steel grade (AISI 304, AISI 630, 12Х21НБТ);
type of rolled metal (sheet, section, pipe);
sheet thickness;
compound;
quality.

You can determine the stainless steel brand and composition in a laboratory setting by contacting a reliable collection point. We have the necessary equipment to analyze the composition, assess the quality and test the radiation activity of non-ferrous scrap. But you can pre-evaluate scrap metal at home.

How to evaluate quality?

The quality of stainless steel depends on various factors - from the amount of additives to the joining method. In places where welds are formed, the anti-corrosion properties of the metal deteriorate significantly, which over time leads to the appearance of rust and gradual destruction of the material.

Painted profiled sheets will have to be cleaned of the coating and sanded, damaging the protective layer on the surface. Accordingly, the metal will become less resistant to moisture, its quality will deteriorate, and therefore the price of such scrap will be lower. You can preliminary evaluate the properties of steel using a salt solution.

It should not leave stains on the surface of high-alloy steel. And water will leave yellowish stains on low-quality stainless steel.

The most expensive types of stainless steel

The cost is affected by the amount of nickel in the alloy: in the cheapest types its content does not exceed 5%. The most expensive are high-alloy alloys containing nickel from 12%. The expensive scrap includes plumbing fittings and rings, wire and various electrical connectors (connectors, adapters, etc.). Matte (a by-product of non-ferrous metallurgy) with a nickel content of over 35% is also highly valued, although it is classified as slag.

But the most common steel grade is A2, containing approximately 10% nickel and 18% chromium. It is usually used to make household items. To find out the exact price, visit our collection point: to evaluate scrap, specialists must inspect the metal, assess the degree of contamination, composition and properties.

Source: https://blog.blizkolom.ru/kak-opredelit-nerzhavejku

How to determine copper at home

Anyone who searches for and sells non-ferrous metal sometimes has doubts about the type of scrap and, accordingly, its true value upon delivery.

Copper is a non-ferrous metal, and brass is an alloy that is typically 70% copper, so it often resembles it.

A mistake can be quite costly. For copper at collection points they give 285-300 rubles, for brass - about 150 .

There are many ways to find out what kind of metal we see - copper or brass, and we will tell you how to distinguish them from each other in this article.

How to determine steel grade

There are simply a huge number of different steel options, each grade is characterized by its own specific features. If the manufacturer has not carried out markings, then you can find out the characteristics of the metal only by independently conducting various tests. We'll talk about this in more detail later.

How to determine steel grade

Methods for determining steel grade

A fairly common question is how to determine the grade of steel. There are several common methods:

The first involves removing chips from the surface, for which a chisel can be used. At high carbon concentrations it will be short and brittle. A decrease in the indicator causes an increase in plasticity. However, it is not possible to accurately determine the brand using this method.
The second method involves hardening the product, after which it is necessary to make cuts. If the material is simply sawed before and after hardening, then it contains a small amount of carbon. Due to the increase in carbon concentration after treatment, the surface becomes too hard.
Determining the steel grade by spark is based on a visual inspection of the sparks that are formed when processing the surface with a grinding wheel. With an increase in the size of the sparks and their number, the hardness index increases, which depends directly on the carbon concentration. Such a test does not give an accurate result, since the main characteristics of the flying chips depend on the force of pressing and some other points. You can find tables that decipher the qualities of a material based on chips.

Spark test methodDevice for determining steel grade

You can also determine the brand by the color of the sparks produced. For this purpose, special tables were compiled. The test can be carried out at home only if the lighting is correct. However, it is impossible to accurately identify the material in this way. The option with alloying elements can also be identified by other performance characteristics, for example, resistance to high humidity or strong magnetism.

In the CIS, the applied designation standards are characterized by the fact that they can be used to indicate the main elements. When considering the issue of decoding the brand, we note the following points:

The abbreviation “St” is often used. In other cases, no abbreviations are used at all, only numbers.
In most cases, the first number indicates the carbon concentration. The following can be used to indicate the amount of alloying components.
The composition may include alloying components that significantly change the properties of the material. An example is the inclusion of chromium, which increases resistance to high humidity.

Classification of steels by purpose

Labeling is deciphered using tables that indicate the designation of the chemical element.

Marking of steels according to international and CIS standards

In order to decipher a brand, you can use a variety of standards. Some alloys are designated by certain symbols that indicate the purpose of the metal.

An example is the following points:

The letter “Ш” is used to designate metals that are used to make bearings. They are characterized by increased wear resistance.
High-quality alloyed workpieces are designated by the letter “L”. Often the symbol is indicated at the end.
“T” is used to designate heat-strengthened rolled products.
High corrosion resistance of the workpiece is determined by the letter “K”.
If copper is included in the composition, then the symbol “D” is used when indicating the brand.
Instrumental can be identified by the letter “U”. They are often used in the manufacture of various tools that are characterized by high wear resistance.
The symbol “P” is indicated to designate alloys that contain tungsten. Such a substance significantly increases the heat resistance of the structure.

By deciphering the brand, you can determine which chemical elements are included in the alloy. The numbers in most cases indicate the concentration, symbols, type of alloy and specific chemical elements.

European steel marking system Carbon steel grades according to GOST and ISO international standards

In conclusion, we note that there is simply a huge number of products on sale; in many cases, the brand is affixed by the manufacturer. It is almost impossible to independently determine the composition without the use of special equipment.

Source: https://stankiexpert.ru/spravochnik/materialovedenie/kak-opredelit-marku-stali.html

How to determine the composition of a metal?

Having selected used tools (needles, files, rasps, braids, etc.), first of all you should determine what grade of steel they are made of. To keep your search as limited as possible, you should know what types of steel a particular tool is made from.

Thus, files can be made of both tool carbon steel (U10, U11, U12, U13) and alloy steel (ShKh6, ShKh9, ShKh15). You can learn more about this from the list of tools below.

The files presented in the KovkaPRO assortment are made of high-alloy steel with a hardness of 64-66HRC

Products made of tool and alloy steel:

Files - U10, U11, U12, U13, ШХ6, ШХ9, ШХ15 Needles - U10, U11, U12 Rasps - U7, U7AShabers - U10, U12 Chisels, chisels - U7, U8 Taps - U10, U11, U12, P9, 9ХС, Р18 Wood drills - 9xsewrla for metal -r9, P18 Exverts-P9, P18, 9XS cutters-P9, P18 Zubila, screwdriver-U7A, U8A, 7XF, 8XFPROPERS-U8 Acernerers-U7A, 7XF, 8XFSHEVENENETEN NE7A, U8APILA-U8 Gapolotnita Rules-UN U8GA, U10 Hacksaw blades – U8, U8A, U9, U9A, U10, U10A, U11, U12 Metal shears – U12AMhammers and sledgehammers – U7, U8 Axes – U7 Scythes, sickles – U7, U8 Forks, teeth (peckers) – U7, U8 rakes

Blacksmith tools – U7, U8

Stage 2: determination of carbon content in steel

How can you determine specifically whether, for example, a file is made of carbon or alloy steel? To do this, you should resort to a simple old method. Craftsmen noticed that small metal shavings obtained when processing metal with an abrasive wheel, when heated, produce a sheaf of sparks, which have their own characteristic features for each metal.

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The “straws” that make up a sheaf of sparks, each brand has its own special ones: long, short, continuous, intermittent, heaped and sparse, smooth or thickened; from each of them small bright stars can be separated, sometimes very abundantly; The brightness of the glow of the sheaf of sparks is taken into account, as well as color shades - from light yellow to dark red.

The higher the carbon content in the steel, the more bright stars there are in the sheaf of sparks. If the steel contains a little carbon, for example about 0.12%, then the sparks coming out from under the abrasive disk will fan out in the form of slightly curved lines of yellow-straw color, with thickenings in the middle and at the end (1, see Fig. on page 105).

Steel containing 0.5% carbon and having an average hardness produces approximately the same sparks, but a small number of stars separate from the place of average thickening (2). Copious sparks with stars (3) are released from the high-carbon tool steel.

Chromium steel has long, orange-red sparks; from them, like thin branches from the main branch, short sparks with stars at the end extend from them at different angles (4). Tungsten steel sparks intermittently, and also has small thickenings at the end (5).

Chrome-tungsten high-speed steel produces both short and long sparks of a dark red color with thickenings at the end (6).

Stage 3: Tool Test

Now let's get back to the file. Before you start testing it, you must wear safety glasses and place a sheet of black-painted plywood near the sanding wheel. On a black background, the sparkling metal is visible much more clearly, and the eyes have to strain less.

If we forcefully run a file over the emery wheel and get abundant sparks of a bright yellow color with many stars separating from them, we can conclude that it is made of high-carbon tool steel (U10-U13). Conversely, a sheaf of orange-red long sparks with branches and stars at the end indicates that the file is made of alloy steel (ШХ6, ШХ9, ШХ15).

Of course, in this way only the approximate chemical composition of steel is determined, but for amateur practice this is quite enough. Knowing that the file is made of tool steel of the indicated grades, the heat treatment mode is determined from the table.

The table shows that the U11-U13 steel from which the file is made is annealed at a temperature of 750°C and then gradually cooled in air. Annealing is carried out in a muffle furnace, forge or in the firebox of a conventional furnace.

It is convenient to anneal metal objects in an electric school muffle furnace, since the built-in thermometer makes it possible to monitor the heating temperature. But the depth of the muffle furnace is limited.

If the file does not fit into it, it is wrapped in several layers of tarpaulin and broken with a strong blow of a hammer.

The broken file is removed from the tarpaulin, annealed in a muffle furnace, and then slowly cooled. The resulting scale often interferes with machining. Therefore, wearing glasses and mittens, they knock it down with a hammer and a chisel.

Annealed and processed tool steel becomes quite soft: it can be easily filed, sawn and forged. With minimal hardness, it has maximum plasticity and viscosity. This makes it possible to make from it gravers for engraving, embossing, chisels, cutters, punches, and other tools for the artistic processing of metal.

Having made the desired tool from a file, it is hardened by heating according to the table to 780°C, followed by cooling in water. After hardening, the steel becomes brittle, so it is tempered: heated to 180°C and cooled in water or machine oil. When tempering, the heating temperature of the metal is controlled by the so-called tarnish colors, which correspond to a certain heating temperature.

Source: https://kovkapro.com/kovka-tehnologiya/kak-opredelit-sostav-metalla-test-po-napilniku/

Ways to determine the type of metal yourself

How to determine a metal and its origin? The question is mainly of interest to jewelry owners who are afraid of purchasing a fake for an impressive amount. You can deal with this problem yourself or contact an expert. The jeweler will conduct an examination, issue an opinion and charge a fee for the work. Authenticity testing can cost from 10 to 20% of the cost of jewelry. If you can’t contact a specialist, then you should try to solve the problem on your own.

Comparison of platinum, silver and white gold

How to check?

Owners of platinum jewelry should remember:

Platinum is an expensive and heavy metal, and small jewelry is often made from it.
Platinum can be replaced with silver, but such a substitution can be recognized by color.
The hardest thing to distinguish from the original is jewelry that has a layer of platinum applied to it.
The mark on the surface of the product should not raise doubts.
Platinum is not afraid of high temperatures and reagents.

The cost of platinum is constantly increasing; there is not much of this metal in the world. Therefore, if in a store a buyer is offered to purchase an impressively sized product made of platinum, and its cost is quite low, he should refuse the purchase. Platinum is not sold cheaply, and jewelry made from it is small; the metal is too heavy.

Platinum Bank Bar

Silver and platinum are similar in appearance, so the expensive metal is often replaced with silver. Such a fake will give itself away with a black tint and plasticity. Silver is not resistant to damage; a mark will remain on its surface, but it will not be possible to spoil a platinum product in this way.

If a layer of platinum is applied to the surface of the product, then a fake can be recognized by its weight. When this is not possible, it will not be possible to determine its quality without causing damage to the jewelry.

Before purchasing, you need to carefully examine the mark; you can use a magnifying glass for this. If all the numbers are clearly visible, most likely the jewelry is really made of platinum.

Due to its chemical properties, platinum is not afraid of high temperatures and acids. When immersed in acid, ammonia and even when exposed to iodine, the product will not change. If you try to heat a ring or earring with a lighter, the temperature of the jewelry will not change immediately. Platinum is a poor conductor of heat, unlike silver.

Gold and silver

At home, gold and silver are most often tested. You can also buy a fake in a jewelry store, but don’t panic.

It is easy to check the authenticity of silver; just immerse it in hot water. The metal will immediately heat up, but will not hold the temperature for long.

Gold jewelry

If you apply a small amount of sulfur ointment to the surface of silver jewelry, the product will immediately darken. This will indicate the authenticity of the metal.

Low-grade silver is easier to distinguish; you just need to hold the item in your hands and then examine your palms. If there are black marks or stains on them, the quality of the silver leaves much to be desired.

Iodine is a universal tool for testing precious metals; a drop of it can resolve all issues. If after the procedure there are streaks left on the surface of the jewelry, it is a fake.

Gold is also tested using iodine. If after the test the metal changes color, absorbs iodine and a stain forms on its surface, this is a sign of a fake or an alloy that contains a large number of other non-precious metals.

Checking gold with a magnet

Gold can also be identified by color: if the jewelry has a red tint, then it probably contains copper. The latter changes color at high humidity and acquires a green tint. Therefore, if gold changes color when in contact with water, it contains copper in large quantities. An exception is red gold, which gets its color by adding copper to the alloy.

A clean piece of paper will help distinguish fake from gold. It is enough to sweep two decorations across its surface at the same time. If the stripes do not have any differences, then they are made of gold.

Only gold that is 585 or higher should be checked for authenticity; other products will not pass the test. And the use of chemical elements during the procedure can ruin the jewelry.

It is difficult to distinguish gilding from gold; for this you can make a notch. The damage will allow us to study the metal at the cut site. If there are no differences, then the jewelry is made of gold.

Another universal method for checking jewelry is a magnet. Noble metals do not react to magnets. If the product behaves differently, then it contains iron or steel.

Some craftsmen have learned to distinguish silver from base metals by assessing the smell - this test is very dubious.

None of the above methods will give a 100% guarantee. You may suspect a fake, but only an expert can accurately determine the quality of the metal. Some silver items are not assayed at all. This is a reason to think, but such a phenomenon does not indicate that it is a fake. You can understand the authenticity of the metal and its quality after some time. If, a few days after purchase, the earrings, ring or bracelet darken, this should be regarded as the first sign of a fake.

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Source: https://DedPodaril.com/lityo/kak-opredelit-metall.html

Metals that are not magnetic - Metals and their processing

Probably everyone had to hold in their hands a piece of jewelry or another object, obviously metal.

But there are methods for approximately determining the type of metal at home. They were used a long time ago, but they have not lost their relevance in our time.

How to determine steel grade?

The creation of metal structures from steel requires the selection of material in accordance with the technical specifications and taking into account the characteristics of steel grades. Determining such characteristics is possible by deciphering the alphanumeric code on the metal marking. However, such a mark cannot always be seen on workpieces; in this case, the determination of the metal grade is carried out using a laboratory method, including using methods based on testing mechanical properties.

Basic methods for determining steel grades

When working with metal, methods for determining the quality of steel are still used today by analyzing its mechanical and physical characteristics. Such methods, unlike laboratory ones, make it possible to approximately determine the qualitative characteristics of the sample, but for work, in particular for welding metal, this is quite enough. Such methods for studying steel grades include:

When it comes to the strength of metal, the chip removal method is used. Its essence is to remove metal shavings using a chisel. Chips that crumble and form into small strips are characteristic of high-carbon steels. Long strips of ductile chips characterize the metal as steel with high ductility.
The quenching method is used to approximate the carbon content of the workpiece. Using a saw blade, cuts are made on the workpiece before and after hardening. If in both cases the metal is easily sawn with a blade, it contains a small amount of carbon. If it is difficult to make cuts after processing, it means that the carbon concentration has increased.
Determining the hardness of a metal by extracting a sheaf of sparks allows you to approximately determine which class of steel the metal belongs to. To do this, surface treatment of the workpiece sample is done on an emery wheel. The shape of the sparks, color, and intensity of the sheaf of sparks determines the hardness of the metal and the carbon content.

Under ordinary home conditions, it is almost impossible to accurately determine the brand and composition of the metal; for this purpose, laboratory tests are carried out, during which a detailed chemical and physical analysis of the metal is performed. The listed methods make it possible to determine only the general characteristics of steel based on its carbon content; the exact characteristics are not determined during such studies.

At the same time, even such a rapid analysis makes it possible to select samples for the manufacture of knives, cutters or parts of machine mechanisms with increased strength and wear resistance.

Marking of steels and their properties

Much more information about the metal can be provided by the markings applied to the samples or the code indicated in the accompanying documents. In the countries of the former USSR, markings for metal for domestic use are indicated in accordance with national state standards developed on the basis of the steel grade of the former USSR. For foreign customers, markings are indicated in accordance with international standards.

For domestic samples, the steel designation is indicated in the first letter code with the signs “St” - steel. The first number after the letter designation indicates the amount of carbon contained in the metal, followed by the codes of alloying components and additives. Letter designations indicate the content of individual additives that significantly affect the quality of the metal, for example, chromium, copper or aluminum.

The description may also indicate separately the purpose of the steel:

Structural;
Instrumental;
Mechanical engineering;
High-speed;
Low alloy;
Wear-resistant;
Magnetic;
Stainless;
Heat resistant.

More detailed information about the chemical and physical properties of such steels can be found in collections of characteristics of grade steels. The reference standards indicated in the reference book provide ideas about the properties of the metal and the possibilities of its application.

Source: https://1nerudnyi.ru/kak-opredelit-marku-stali-10/