What is stronger: steel or titanium?

Which metal is considered the most durable?

Titan was discovered at the end of the 18th century by independent scientists from England and Germany. In the periodic table of elements D.I. Mendeleev titanium was located in group 4 with atomic number 22. For quite a long time, scientists did not see any prospects in titanium, since it was very fragile. But in 1925, Dutch scientists I. de Boer and A. Van Arkel were able to obtain pure titanium in the laboratory, which became a real breakthrough in all industries.

Properties of titanium

Pure titanium turned out to be incredibly technological. It has ductility, low density, high specific strength, corrosion resistance, and strength when exposed to high temperatures.

Titanium is twice as strong as steel and six times as strong as aluminum. Titanium is indispensable in supersonic aviation. After all, at an altitude of 20 km, the plane reaches a speed that exceeds the speed of sound three times. In this case, the temperature of the aircraft body heats up to 300°C.

Only titanium alloys can withstand such conditions.

Titanium shavings are a fire hazard, and titanium dust can generally explode. During an explosion, the flash point can reach 400°C.

The most durable on the planet

Titanium is so light and strong that its alloys are used to make aircraft and submarine hulls, body armor and tank armor, and are also used in nuclear technology. Another remarkable property of this metal is its passive effect on living tissue. Osteoprostheses are made only from titanium. Semi-precious stones and jewelry are made from some titanium compounds.

The chemical industry has also not ignored titanium. In many aggressive environments, metal does not corrode. Titanium dioxide is used to make white paint, in the production of plastic and paper, and as a food additive E171.

On the scale of metal hardness, titanium is second only to platinum metals and tungsten.

Distribution and stocks

Titanium is a fairly common metal. In nature, according to this indicator, it ranks tenth. The earth's crust contains about 0.57% titanium. At the moment, scientists know over a hundred minerals that contain metal. Its deposits are scattered almost all over the world. Titanium mining is carried out in China, South Africa, Russia, Ukraine, India and Japan.

Progress

For several years now, scientists have been conducting research on a new metal, which was called “liquid metal”. This invention claims to be the new, most durable metal on the planet. But it has not yet been obtained in solid form.

Source: https://www.kakprosto.ru/kak-825770-kakoy-metall-schitaetsya-samym-prochnym

Strength of titanium and steel

Which watch is better - titanium or steel? [contact-form-7 404 “Not Found”]

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Today, watches play the role of an indispensable accessory for every modern person, with the help of which you can advantageously emphasize your high status, as well as stand out from the gray mass. Therefore, it is very important to choose the best option. Watches made of titanium and steel are especially popular due to their excellent performance characteristics.

Steel watch

Stainless steel watches are the most common. Mass and relatively inexpensive production of this material allows us to offer watches in a wide price range.

The inertness of steel protects the case and parts of the watch mechanism from oxidation and “aging”.

Steel is characterized by increased viscosity, which makes it resistant to external damage: upon impact, steel watches do not split or crack.

There are quite a few formulas of steel alloys; the best steel in terms of strength, used for the manufacture of watch cases, is low-carbon 316L.

Advantages:

• impact resistance;
• ease of use;
• ratio of quality and price;
• wear resistance;
• If scratches occur, you can easily restore the appearance by polishing.

Flaws:

Titanium in watchmaking

The complexity of the process of mining and processing titanium ore. The production of rough blanks is expensive - the technology involves melting titanium at high temperatures and casting in a vacuum.

Difficulty in machining the product due to the high strength of titanium.

All this significantly affects the cost of the final product, and until the end of the 20th century, the use of titanium in watchmaking was considered unprofitable.

But as has happened more than once, the military set the pace. At the end of the 80s of the last century, for the troops of the German Bundeswehr, IWC produced a watch in a titanium case - the Ocean Bund.

These models are still in great demand among collectors, especially the “Diver – Sapper” version (German: Minentaucher).

Source: https://steelfactoryrus.com/prochnost-titana-i-stali/

The hardest metal in the world

Our world is full of amazing facts that are interesting to many people. The properties of various metals are no exception. Among these elements, of which there are 94 in the world, there are the most ductile and malleable, and there are also those with high electrical conductivity or a high resistance coefficient. This article will talk about the hardest metals, as well as their unique properties.

Iridium ranks first in the list of metals that are distinguished by the greatest hardness. It was discovered at the beginning of the 19th century by the English chemist Smithson Tennant. Iridium has the following physical properties:

• has a silvery-white color;
• its melting point is 2466 °C;
• boiling point – 4428 oC;
• resistance – 5.3·10−8Ohm·m.

Because iridium is the hardest metal on the planet, it is difficult to process. But it is still used in various industrial fields. For example, it is used to make small balls that are used in pen nibs. Iridium is used to make components for space rockets, some parts for cars, and more.

Iridium

Very little iridium occurs in nature. Findings of this metal are a kind of evidence that meteorites fell in the place where it was discovered. These cosmic bodies contain significant amounts of metal. Scientists believe that our planet is also rich in iridium, but its deposits are closer to the Earth's core.

Ruthenium

The second position on our list goes to ruthenium. The discovery of this inert silvery metal belongs to the Russian chemist Karl Klaus, which was made in 1844. This element belongs to the platinum group. It is a rare metal. Scientists have been able to establish that there is approximately 5 thousand tons of ruthenium on the planet. It is possible to extract approximately 18 tons of metal per year.

Ruthenium

Due to its limited quantity and high cost, ruthenium is rarely used in industry. It is used in the following cases:

• a small amount of it is added to titanium to improve corrosion properties;
• its alloy with platinum is used to make electrical contacts that are highly resistant;
• ruthenium is often used as a catalyst for chemical reactions.

Tantalum

A metal called tantalum, discovered in 1802, takes third place on our list. It was discovered by the Swedish chemist A. G. Ekeberg. For a long time it was believed that tantalum is identical to niobium. But the German chemist Heinrich Rose managed to prove that these are two different elements. Scientist Werner Bolton from Germany was able to isolate tantalum in its pure form in 1922. This is a very rare metal. The largest deposits of tantalum ore were discovered in Western Australia.

Tantalum

Due to its unique properties, tantalum is a highly sought-after metal. It is used in various fields:

• in medicine, tantalum is used to make wire and other elements that can hold tissue together and even act as a bone substitute;
• alloys with this metal are resistant to aggressive environments, which is why they are used in the manufacture of aerospace equipment and electronics;
• tantalum is also used to create energy in nuclear reactors;
• the element is widely used in the chemical industry.

Chromium

Chromium is one of the hardest metals. It was discovered in Russia in 1763 in a deposit in the Northern Urals. It has a bluish-white color, although there are cases where it is considered a black metal. Chrome cannot be called a rare metal. The following countries are rich in its deposits:

• Kazakhstan;
• Russia;
• Madagascar;
• Zimbabwe.

Chromium

There are chromium deposits in other countries as well. This metal is widely used in various branches of metallurgy, science, mechanical engineering and others.

Beryllium

The fifth position in the list of the hardest metals goes to beryllium. Its discovery belongs to the chemist Louis Nicolas Vauquelin from France, which was made in 1798. This metal has a silvery-white color.

Despite its hardness, beryllium is a brittle material, which makes it very difficult to process. It is used to create high-quality loudspeakers. It is used to create jet fuel and refractory materials.

The metal is widely used in the creation of aerospace technology and laser systems. It is also used in nuclear energy and in the manufacture of X-ray equipment.

Beryllium

Osmium

The list of the hardest metals also includes osmium. It is an element belonging to the platinum group, and its properties are similar to iridium. This refractory metal is resistant to aggressive environments, has a high density, and is difficult to process.

It was discovered by the scientist Smithson Tennant from England in 1803. This metal is widely used in medicine. Elements of pacemakers are made from it, and it is also used to create the pulmonary valve.

It is also widely used in the chemical industry and for military purposes.

Osmium

The transition silver metal rhenium takes the seventh position on our list. The assumption about the existence of this element was made by D.I. Mendeleev in 1871, and chemists from Germany managed to discover it in 1925.

Just 5 years after this, it was possible to establish the extraction of this rare, durable and refractory metal. At that time, it was possible to obtain 120 kg of rhenium per year. Now the amount of annual metal production has increased to 40 tons. It is used for the production of catalysts.

It is also used to make electrical contacts that can self-clean.

Rhenium

Tungsten

Silver-gray tungsten is not only one of the hardest metals, it also leads in refractoriness. It can only be melted at a temperature of 3422 °C.

Due to this property, it is used to create incandescent elements. Alloys made from this element have high strength and are often used for military purposes. Tungsten is also used to make surgical instruments.

It is also used to make containers in which radioactive materials are stored.

Tungsten

Uranus

One of the hardest metals is uranium. It was discovered in 1840 by the chemist Peligo. D.I. Mendeleev made a great contribution to the study of the properties of this metal. The radioactive properties of uranium were discovered by the scientist A. A. Becquerel in 1896. Then a chemist from France called the detected metal radiation Becquerel rays. Uranium is often found in nature. The countries with the largest deposits of uranium ore are Australia, Kazakhstan and Russia.

Uranus

The final place in the top ten hardest metals goes to titanium. For the first time this element was obtained in its pure form by the chemist J. Ya. Berzelius from Sweden in 1825. Titanium is a lightweight silver-white metal that is highly durable and resistant to corrosion and mechanical stress. Titanium alloys are used in many branches of mechanical engineering, medicine and the chemical industry.

Titanium

Source: https://topkin.ru/best/nauka/samyiy-tverdyiy-metall/

Which watch is better - titanium or steel? 19446 reads:

A metal case is a classic solution for wristwatches. There are several dozen alloys from which the watch itself and the bracelet can be made. The most popular ones are with titanium and steel. These metals are rarely coated, which is why watches made from them have a characteristic light gray color. Externally, steel and titanium can only be distinguished by a specialist, but in terms of their characteristics they differ significantly.

 Steel watch

Stainless steel watches are the most common. Mass and relatively inexpensive production of this material allows us to offer watches in a wide price range. The inertness of steel protects the case and parts of the watch mechanism from oxidation and “aging”.

Steel is characterized by increased viscosity, which makes it resistant to external damage: upon impact, steel watches do not split or crack.

There are quite a few formulas of steel alloys; the best steel in terms of strength, used for the manufacture of watch cases, is low-carbon 316L.

 Advantages:

· impact resistance;

· unpretentiousness in operation;

· ratio of quality and price;

· wear resistance;

· If scratches occur, the appearance can be easily restored by polishing.

Flaws:

· heavy weight.

 Watches with titanium case

Titanium has been used in watch production relatively recently - since the 50s, although this material began to be “tamed” back in the 18th century. Due to its physical properties, titanium has found wide application in industry, in particular in the production of aircraft and helicopters.

At first, only some parts of the watch mechanism were made from titanium alloys, later - bracelets and the case. Such alloys are characterized by absolute inertness, i.e. they do not interact with other substances, do not rust or change color.

Moreover, titanium alloys do not react to magnetic influences, which provides the more precise movement required for professional chronographs.

Titanium is also considered the safest metal; alloys with it, unlike stainless steel, do not cause allergic reactions.

 Advantages:

· in alloys, titanium is 5 times stronger than steel;

· withstands pressure of 1000 MPa;

· light weight;

· 100% corrosion resistance;

· scratches are less noticeable on titanium, although they appear more easily than on steel;

· hypoallergenic;

· more accurate movement.

Flaws:

· plasticity;

· high price;

· the danger of the lid “merging” with the body due to the tendency to diffusion, that is, the lid must be opened periodically;

· difficult care.

Source: https://www.cpv.ru/modules/publisher/item.php?itemid=1008

I will buy Titan 200 Steel:VT 1-0 St. Petersburg (application No. 127017 dated 01/21/2020 14:15)

Supplier prices Tenders Buyer requests ads Print application Name Quantity Length Steel Price (no more) Note 1 Titanium 200 1 m/p — VT 1-0 — Titan VT 1-0 f.200 -1m 2 Titanium 40 1 m/p — VT 1-0 — Titan VT 1-0 f.40 -1m Comment on the application: Urgent Titan VT 1-0 f.40 -1m Titan VT 1-0 f.200 -1m Customer To authorize yourself as a rolled metal supplier, we suggest you post your price list on our portal. After posting the price list, you will have full access to Buyers' Applications. You will receive direct calls from customers to your office and transitions to your website from the pages of the METAL100.RU portal The buyer’s transition to your website is highly converting, since the visitor has already chosen the size of rolled metal he needs, found out your price and went to your website to make a purchase. An example of placing a supplier price list - Titan RATING METAL100.RU - http://top.mail.ru/Rating/Industry-Ferrous/Month/Visitors/ If you are ready to log in, please send us an email to [email protected] containing the following information: — your website address (if available); — link address for downloading the current price list in Excel format. (if there is a link, prices are updated automatically twice a day), if the link or this format is not on the site, send your price list in Excel format. to [email protected] . (updating prices at your request); — Your details for invoicing. More details - Services section: http://metal100.ru/service/ More information about placement in the Advertising section: http://metal100.ru/advertising/

Source: http://rostov-na-donu.metal100.ru/orders/127017

Which watch is better - titanium or steel? [contact-form-7 404

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Today, watches play the role of an indispensable accessory for every modern person, with the help of which you can advantageously emphasize your high status, as well as stand out from the gray mass. Therefore, it is very important to choose the best option. Watches made of titanium and steel are especially popular due to their excellent performance characteristics.

Tensile and tensile strength of a material - what is it, how is the fluidity of the metal and the tensile strength of steel measured?

14Nov

articles

When constructing objects, it is imperative to use calculations that include detailed characteristics of building materials. Otherwise, too much, unbearable load may be placed on the support, which will cause destruction. Today we’ll talk about the tensile strength of a material at break and tension, we’ll tell you what it is and how to work with this indication.

Tensile strength

PP - we will use this abbreviation, and we can also talk about the official combination “temporary resistance” - this is the maximum mechanical force that can be applied to an object before its destruction begins. In this case, we are not talking about chemical effects, but we mean that heating, unfavorable climatic conditions, and a certain environment can either improve the properties of the metal (as well as wood, plastic) or worsen it.

No engineer uses extreme values ​​when designing, because it is necessary to leave a permissible error - for environmental factors, for the duration of operation. We told you what is called tensile strength, now let’s move on to the specifics of the definition.

How is the strength test performed?

Initially there were no special events. People took an item, used it, and as soon as it broke, they analyzed the breakdown and reduced the load on a similar product. Now the procedure is much more complicated, however, until now the most objective way to find out PP is the empirical way, that is, experiments and experiments.

All tests are carried out under special conditions with a large amount of precise equipment that records the condition and characteristics of the experimental material. Usually it is fixed and experiences various influences - tension, compression.

They are performed by instruments with high precision - every thousandth of a newton of the applied force is noted. At the same time, each deformation is recorded as it occurs. Another method is not laboratory, but computational.

But usually mathematical analysis is used in conjunction with testing.

Definition of the term

The sample is stretched on a testing machine. In this case, first it lengthens in size, and the cross-section becomes narrower, and then a neck is formed - the place where the thinnest diameter is, this is where the workpiece will rupture. This is true for ductile alloys, while brittle alloys, such as cast iron and hard steel, stretch very slightly without necking. Let's take a closer look at the video:

Types of PP

Tensile strength is determined by various influences, according to this it is classified according to:

• compression – mechanical pressure forces act on the sample;
• bending - the part is bent in different directions;
• torsion – suitability for use as a rotating shaft is checked;
• stretching - we gave a detailed example of testing above.

Tensile strength of steel

Steel structures have long replaced other materials, as they have excellent performance characteristics - durability, reliability and safety. Depending on the technology used, it is divided into brands. From the most common with a PP of 300 MPa, to the hardest with a high carbon content - 900 MPa. This depends on two indicators:

• What heat treatment methods were used - annealing, hardening, cryotreatment.
• What impurities are contained in the composition. Some are considered harmful, they are discarded for the purity of the alloy, and others are added to strengthen them.

Yield strength and tensile strength

The new term is designated in the technical literature by the letter T. The indicator is relevant exclusively for plastic materials and indicates how long a sample can be deformed without increasing the external load on it.

Usually, after overcoming this threshold, the crystal lattice changes greatly and is rearranged. The result is plastic deformation. They are not undesirable; on the contrary, self-strengthening of the metal occurs.

Fatigue of steel

The second name is endurance limit. It is denoted by the letter R. This is a similar indicator, that is, it determines what force can act on an element, but not in a single case, but in a cycle. That is, certain pressures are applied to the experimental standard cyclically, over and over again. The average number of repetitions is 10 to the seventh power. This is exactly how many times the metal must withstand the impact without deformation or loss of its characteristics.

If you carry out empirical tests, it will take a lot of time - you need to check all the force values, applying it over many cycles. Therefore, the coefficient is usually calculated mathematically.

Proportionality limit

This is an indicator that determines the duration of the loads applied to the deformation of the body. In this case, both values ​​should change to different degrees according to Hooke’s law. In simple words: the greater the compression (tension), the more the sample is deformed.

The value of each material lies between absolute and classical elasticity. That is, if the changes are reversible after the force ceases to act (the shape becomes the same - for example, compression of a spring), then such parameters cannot be called proportional.

How are the properties of metals determined?

They check not only what is called tensile strength, but also other characteristics of steel, for example, hardness. The tests are carried out as follows: a ball or cone made of diamond, the most durable rock, is pressed into the sample.

The stronger the material, the smaller the mark left. Deeper, wider-diameter prints are left on soft alloys. Another experience - for a blow. The impact occurs only after a pre-made cut on the workpiece.

That is, the destruction is checked for the most vulnerable area.

Mechanical properties

There are 5 characteristics:

• The tensile and tensile strength of steel is temporary resistance to external forces, stress arising internally.
• Plasticity is the ability to deform, change shape, but maintain the internal structure.
• Hardness – willingness to meet harder material without causing significant damage.
• Impact strength is the ability to resist impacts.
• Fatigue is the duration of preservation of qualities under the influence of cyclic loads.

Strength classes and their designations

All categories are written down in regulatory documents - GOSTs, according to which all Russian entrepreneurs produce any rolled metal and other metal products. Here is the correspondence between the designation and parameter in the table:

Class	Tensile strength, N/mm2
265	430
295	430
315	450
325	450
345	490
355	490
375	510
390	510
440	590

We see that for some classes the PP indicators remain the same, this is explained by the fact that, with equal values, their fluidity or relative elongation may differ. Depending on this, different maximum thickness of rolled metal is possible.

Specific strength formula

R with the index “y” is the designation of this parameter in physics. It is calculated as PP (in writing – R) divided by density – d. That is, this calculation has practical value and takes into account theoretical knowledge about the properties of steel for use in life. Engineers can tell how the temporary resistance changes depending on the mass and volume of the product. It is logical that the thinner the sheet, the easier it is to deform.

The formula looks like this:

Ry = R/d

Here it would be logical to explain how the specific tensile strength is measured. In N/mm2 - this follows from the proposed calculation algorithm.

Using the properties of metals

Two important indicators - plasticity and PP - are interrelated. Materials with a large first parameter degrade much more slowly. They change their shape well and are subjected to various types of metal processing, including die stamping - that’s why car body elements are made from sheets. With low ductility, alloys are called brittle. They can be very hard, but at the same time have poor stretching, bending and deformation, for example, titanium.

Resistance

There are two types:

• Regulatory - prescribed for each type of steel in GOSTs.
• Calculated – obtained after calculations in a specific project.

The first option is rather theoretical; the second is used for practical tasks.

Ways to increase strength characteristics

There are several ways to do this, two main ones:

• addition of impurities;
• heat treatment, for example, hardening.

Sometimes they are used together.

General information about steels

All of them have chemical and mechanical properties. Below we’ll talk in more detail about ways to increase strength, but first, let’s present a diagram showing all the varieties:

Also watch a more detailed video:

All of them have chemical and mechanical properties. Below we’ll talk in more detail about ways to increase strength, but first, let’s present a diagram showing all the varieties:

Carbon

The higher the carbon content of a substance, the higher the hardness and the lower the ductility. But the composition should not contain more than 1% of the chemical component, since a larger amount leads to the opposite effect.

Manganese

A very useful additive, but with a mass fraction of no more than two percent. Mn is usually added to improve machinability. The material becomes more susceptible to forging and welding. This is due to the displacement of oxygen and sulfur.

Silicon

Effectively increases strength characteristics without affecting ductility. The maximum content is 0.6%, sometimes 0.1% is enough. Combines well with other impurities; together, they can increase corrosion resistance.

Nitrogen and oxygen

If they get into the alloy, but worsen its characteristics, they try to get rid of them during manufacturing.

Alloying Additives

You can also find the following impurities:

• Chrome – increases hardness.
• Molybdenum – protects against rust.
• Vanadium – for elasticity.
• Nickel – has a good effect on hardenability, but can lead to brittleness.

These and other chemicals must be used in strict proportions according to the formulas. In the article we talked about tensile strength (short-term resistance) - what it is and how to work with it. They also gave several tables that you can use while working. To finish, let's watch the video:

To clarify the information you are interested in, contact our managers by phone 8 (908) 135-59-82; (473) 239-65-79; 8 (800) 707-53-38. They will answer all your questions.

Source: http://www.rocta.ru/info/predel-prochnosti-materialov-razryv-metallov-pri-rastyazhenii-i-szhatii-chto-ehto-takoe-vidy-foto/

Strength of titanium compared to steel

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Many people are interested in the slightly mysterious and not fully studied titanium - a metal whose properties are somewhat ambiguous. Metal is both the strongest and most fragile.

It was discovered by two scientists with a difference of 6 years - the Englishman W. Gregor and the German M. Klaproth.
The name titan is associated, on the one hand, with the mythical titans, supernatural and fearless, and on the other hand, with Titania, the queen of fairies. This is one of the most common materials in nature, but the process of obtaining pure metal is particularly complex.

Titanium and competition with other metals

This metal is constantly compared to aluminum and iron alloys. Many chemical properties of titanium are significantly better than those of competitors:

1. In terms of mechanical strength, titanium is 2 times greater than iron, and aluminum 6 times.
   Its strength increases with decreasing temperature, which is not observed among competitors. The anti-corrosion characteristics of titanium significantly exceed those of other metals.
2. At ambient temperatures the metal is completely inert. But when the temperature rises above +200°C, the substance begins to absorb hydrogen, changing its characteristics.
3. At higher temperatures, titanium reacts with other chemical elements. It has a high specific strength, which is 2 times higher than the properties of the best iron alloys.
4. The anti-corrosion properties of titanium significantly exceed those of aluminum and stainless steel.
5. The substance does not conduct electricity well. Titanium has an electrical resistivity 5 times higher than that of iron, 20 times higher than that of aluminum, and 10 times higher than magnesium.
6. Titanium is characterized by low thermal conductivity, this is due to its low coefficient of thermal expansion. It is 3 times less than that of iron, and 12 times less than that of aluminum.

How is titanium obtained?

The material ranks 10th in distribution in nature. There are about 70 minerals containing titanium in the form of titanic acid or titanium dioxide. The most common of them and containing a high percentage of metal derivatives are:

The main deposits of titanium ores are located in the USA, Great Britain, Japan, large deposits have been discovered in Russia, Ukraine, Canada, France, Spain, and Belgium.

Extracting metal from them is very expensive. Scientists have developed 4 methods for producing titanium, each of which is functional and effectively used in industry:

1. Magnesium-thermal method. The extracted raw materials containing titanium impurities are processed and titanium dioxide is obtained. This substance is subjected to chlorination in mine or salt chlorinators at elevated temperatures. The process is very slow and is carried out in the presence of a carbon catalyst. In this case, solid dioxide is converted into a gaseous substance - titanium tetrachloride. The resulting material is reduced with magnesium or sodium. The alloy formed during the reaction is heated in a vacuum unit to ultra-high temperatures. As a result of the reaction, magnesium and its compounds with chlorine evaporate. At the end of the process, a sponge-like material is obtained. It is melted and high quality titanium is obtained.
2. Calcium hydride method. The ore is subjected to a chemical reaction to produce titanium hydride. The next stage is the separation of the substance into its components. Titanium and hydrogen are released during heating in vacuum units. At the end of the process, calcium oxide is obtained, which is washed with weak acids. The first two methods relate to industrial production. They make it possible to obtain pure titanium in the shortest possible time at relatively low costs.
3. Electrolysis method. Titanium compounds are exposed to high current. Depending on the feedstock, compounds are divided into components: chlorine, oxygen and titanium.
4. Iodide method or refining. Titanium dioxide obtained from minerals is doused with iodine vapor. As a result of the reaction, titanium iodide is formed, which is heated to a high temperature - +1300+1400°C and is exposed to electric current. In this case, the following components are isolated from the source material: iodine and titanium. The metal obtained by this method has no impurities or additives.

Source: https://ostwest.su/instrumenty/prochnost-titana-v-sravnenii-so-stalju.php/

Characteristics of titanium-based alloys, metal properties and applications

Titanium was originally named "gregorite" by British chemist Reverend William Gregor, who discovered it in 1791. Titanium was then independently discovered by the German chemist M. H. Klaproth in 1793. He named it titan after the Titans of Greek mythology - "the embodiment of natural strength." It was not until 1797 that Klaproth discovered that his titanium was an element previously discovered by Gregor.

Titanium is a chemical element with the symbol Ti and atomic number 22. It is a shiny metal with a silvery color, low density and high strength. It is resistant to corrosion in seawater and chlorine.

The element is found in a number of mineral deposits, mainly rutile and ilmenite, which are widespread in the Earth's crust and lithosphere.

Titanium is used to produce strong light alloys. The metal's two most useful properties are corrosion resistance and its hardness-to-density ratio, the highest of any metallic element. In its unalloyed state, this metal is as strong as some steels, but less dense.

Physical properties of metal

It is a strong metal with low density, quite ductile (especially in an oxygen-free environment), shiny and metalloid white. Its relatively high melting point of over 1650 °C (or 3000 °F) makes it useful as a refractory metal. It is paramagnetic and has fairly low electrical and thermal conductivity.

On the Mohs scale, the hardness of titanium is 6. According to this indicator, it is slightly inferior to hardened steel and tungsten.

Commercially pure (99.2%) titanium has an ultimate tensile strength of about 434 MPa, which is similar to common low-grade steel alloys, but titanium is much lighter.

Chemical properties of titanium

Like aluminum and magnesium, titanium and its alloys immediately oxidize when exposed to air. It reacts slowly with water and air at ambient temperatures because it forms a passive oxide coating that protects the bulk metal from further oxidation.

Atmospheric passivation gives titanium excellent corrosion resistance almost equivalent to platinum. Titanium is able to resist attack from dilute sulfuric and hydrochloric acids, chloride solutions and most organic acids.

Titanium is one of the few elements that burns in pure nitrogen, reacting at 800°C (1470°F) to form titanium nitride. Due to their high reactivity with oxygen, nitrogen and some other gases, titanium filaments are used in titanium sublimation pumps as absorbers for these gases. These pumps are inexpensive and reliably produce extremely low pressures in ultra-high vacuum systems.

Common titanium-containing minerals are anatase, brookite, ilmenite, perovskite, rutile and titanite (sphene). Of these minerals, only rutile and ilmenite are of economic importance, but even these are difficult to find in high concentrations.

Titanium is found in meteorites and has been found in the Sun and M-type stars with surface temperatures of 3200°C (5790°F).

Currently known methods for extracting titanium from various ores are labor-intensive and expensive.

Production and manufacturing

Currently, about 50 grades of titanium and titanium alloys have been developed and used. Today, 31 classes of titanium metal and alloys are recognized, of which classes 1–4 are commercially pure (unalloyed).

They differ in tensile strength depending on oxygen content, with class 1 being the most ductile (lowest tensile strength with 0.18% oxygen) and class 4 the least ductile (highest tensile strength with 0.40% oxygen). ).

The remaining classes are alloys, each of which has specific properties:

• plastic;
• strength;
• hardness;
• electrical resistance;
• specific corrosion resistance and their combinations.

In addition to these specifications, titanium alloys are also manufactured to meet aerospace and military specifications (SAE-AMS, MIL-T), ISO standards and country-specific specifications, as well as end-user requirements for aerospace, military, medical and industrial applications.

A commercially pure flat product (sheet, slab) can be easily formed, but processing must take into account the fact that the metal has a "memory" and a tendency to bounce back. This is especially true for some high-strength alloys.

Titanium is often used to make alloys:

• with aluminum;
• with vanadium;
• with copper (for hardening);
• with iron;
• with manganese;
• with molybdenum and other metals.

Areas of use

Titanium alloys in sheet, plate, rod, wire, and casting form find applications in industrial, aerospace, recreational, and emerging markets. Powdered titanium is used in pyrotechnics as a source of bright burning particles.

Because titanium alloys have a high tensile strength-to-density ratio, high corrosion resistance, fatigue resistance, high crack resistance, and the ability to withstand moderately high temperatures, they are used in aircraft, armor, naval vessels, spacecraft, and missiles.

For these applications, titanium is alloyed with aluminum, zirconium, nickel, vanadium and other elements to produce a variety of components, including critical structural members, firewalls, landing gear, exhaust pipes (helicopters) and hydraulic systems. In fact, about two-thirds of titanium metal produced is used in aircraft engines and frames.

Because titanium alloys are resistant to seawater corrosion, they are used for propeller shafts, heat exchanger rigging, etc. These alloys are used in housings and components of ocean surveillance and monitoring devices for science and the military.

Specific alloys are used in oil and gas wells and nickel hydrometallurgy for their high strength. The pulp and paper industry uses titanium in process equipment exposed to aggressive environments such as sodium hypochlorite or wet chlorine gas (in bleaching). Other applications include ultrasonic welding, wave soldering.

Additionally, these alloys are used in automotive applications, especially in automobile and motorcycle racing where low weight, high strength and stiffness are essential.

Titanium is used in many sporting goods: tennis rackets, golf clubs, lacrosse shafts; cricket, hockey, lacrosse and football helmets, as well as bicycle frames and components.

Due to its durability, titanium has become more popular for designer jewelry (particularly titanium rings). Its inertness makes it a good choice for people with allergies or those who will be wearing jewelry in environments such as swimming pools.

Titanium is also alloyed with gold to produce an alloy that can be sold as 24 karat gold because 1% Ti alloyed is not enough to require a lower grade.

The resulting alloy is approximately the hardness of 14 karat gold and is stronger than pure 24 karat gold.

Precautionary measures

Titanium is non-toxic even in large doses . Whether in powder or metal filing form, it poses a serious fire hazard and, if heated in air, an explosion hazard.

Properties and applications of titanium alloys

Below is an overview of the most commonly found titanium alloys, divided into classes, their properties, advantages and industrial applications.

7th grade

Grade 7 is mechanically and physically equivalent to Grade 2 pure titanium, except for the addition of the intermediate element palladium, making it an alloy. It has excellent weldability and elasticity, the most corrosion resistance of all alloys of this type.

Class 7 is used in chemical processes and manufacturing equipment components.

Grade 11

Class 11 is very similar to Class 1, except for the addition of palladium to improve corrosion resistance, making it an alloy.

Other beneficial properties include optimum ductility, strength, toughness and excellent weldability. This alloy can be used especially in applications where corrosion is a problem:

• chemical treatment;
• production of chlorates;
• desalination;
• marine applications.

Ti 6Al-4V, class 5

Ti 6Al-4V alloy, or grade 5 titanium, is the most commonly used. It accounts for 50% of total titanium consumption worldwide.

Ease of use lies in its many advantages. Ti 6Al-4V can be heat treated to increase its strength. This alloy has high strength with low weight.

It is the best alloy for use in several industries such as aerospace, medical, marine and chemical processing. It can be used to create:

• aircraft turbines;
• engine components;
• aircraft structural elements;
• aerospace fasteners;
• high-performance automatic parts;
• sports equipment.

Ti 6AL-4V ELI, class 23

Class 23 - surgical titanium. Ti 6AL-4V ELI alloy, or grade 23, is a higher purity version of Ti 6Al-4V. It can be made from rolls, threads, wires or flat wires. It is the best choice for any situation where a combination of high strength, low weight, good corrosion resistance and high toughness is required. It has excellent damage resistance.

It can be used in biomedical applications such as implantable components due to its biocompatibility, good fatigue resistance. It can also be used in surgical procedures to make the following structures:

• orthopedic pins and screws;
• ligature clamps;
• surgical staples;
• springs;
• orthodontic devices;
• cryogenic vessels;
• bone fixation devices.

12th grade

Titanium grade 12 has excellent high-quality weldability. It is a high-strength alloy that provides good strength at high temperatures. Grade 12 titanium has characteristics similar to 300 series stainless steels.

Its ability to be shaped in a variety of ways makes it useful in many applications. The alloy's high corrosion resistance also makes it invaluable for manufacturing equipment. Class 12 can be used in the following industries:

• heat exchangers;
• hydrometallurgical applications;
• chemical production at elevated temperatures;
• maritime and air components.

Ti5Al-2.5Sn

Ti 5Al-2.5Sn is an alloy that can provide good weldability with stability. It also has high temperature stability and high strength.

Ti 5Al-2.5Sn is mainly used in the aviation sector and also in cryogenic applications.

Source: https://tokar.guru/metally/splavy/harakteristika-i-primenenie-titana-i-splavov-na-ego-osnove.html

Solar power plants. What cannot be foreseen

“There are still a lot of big failures ahead,” says Yale University economics professor Kenneth Gillingham, who has studied energy issues as part of the White House Council of Economic Advisers.

Failures and financial losses when lending to renewable energy projects are inevitable. Supporters of government investment in them are confident of this. In any innovation, it is difficult to foresee all the pitfalls and force majeure situations.

USA

The 110 MW Crescent Dunes solar thermal power plant has been shut down after losing its last customer. Bloomberg reports this. At one time, about $1 billion was invested in the solar thermal project, including loans from the state.

Crescent Dunes Solar Thermal Power Plant. bloomberg.com

Construction of the Crescent Dunes solar thermal station began in 2011: the developers planned that the facility would generate electricity 24 hours a day. In addition, it was believed that thanks to the thermal energy storage system in molten salt, the station would be able to supply energy even during peak hours.

During operation of a solar thermal station, mirrors arranged in a circle focus a concentrated beam of sunlight onto a thermal element (a vessel with water or salt), which is located in the center of the object.

The facility was put into operation in September 2015, but in October 2016 it had to be stopped due to a leak in the molten salt tank. It was possible to resume electricity generation only in July 2017.

In 2019, the power plant lost its only energy buyer, NV Energy, part of Warren Buffett's empire, which accused Crescent Dunes of insufficient reliability and inability to supply the required volumes of electricity. As a result of this loss, the facility was shut down.

Crescent Dunes generated energy at $135/MWh, photovoltaics can do this in Nevada at $30/MWh. bloomberg.com

Currently, the station's debt to the state is estimated at $737 million. The facility's management is looking for a buyer who can revive the station or dismantle it.

In addition, the station, in fact, became a victim of scientific progress: in the early 2010s, when the project was just being created, photovoltaic generation was almost 4 times more expensive than solar thermal. Today, the price of photovoltaic generation has become 3-4 times cheaper.

Australia

Forest fires have dramatically affected the operation of solar power plants. Rooftop solar panels in Australia produced 45% less electricity due to massive fires that swept across the country.

This is stated in a message from Solar Analytics, writes Domain Media. The most severe decrease in the power of photovoltaic modules occurred on the New Year, on the eve of severe fires.

Forest fires in Australia. telegraph.co.uk.

Experts also said that the decline in panel production was not limited to days when the sky was filled with smog from fires. In addition, even panels that were located at a great distance from the fire sources were damaged by fires. The main reason for the deterioration of the performance of photovoltaic models was the layer of ash that formed on the surface of the panels.

The publication recalls that on average, dust and particulate matter can reduce the efficiency of solar panels by 25%. Relevant studies were conducted in the regions of India and China. In the case of two countries, air pollution was caused by emissions from the combustion of fossil fuels, in particular coal.

Found a typo? Select a fragment and press Ctrl+Enter.

Source: https://naukatehnika.com/solnechnye-elektrostancii-to-chto-nelzya-predvidet.html

TOP 15 best men's wristwatches ⌚ - selection rules, review and characteristics

Sometimes it may seem that wristwatches have lost their relevance. Today, every person cannot imagine life without a mobile phone, which will not only show the time, but also synchronize it with the Greenwich standard, and even wake you up with an alarm at the right moment. Also, the standard set of operating systems for all smartphones includes a stopwatch and timer.

But in fact, men's wristwatches, having lost slightly in popularity, have gained in value and status. They continue to be a stylish accessory and an indicator of good taste. In addition, the watch will not fail far from an electrical outlet, when every percent of the smartphone’s charge counts.

In this article we will tell you how to choose a men's wristwatch and introduce you to the TOP 15 rating of the best men's watches.

How to choose a men's watch

Options for choosing a men's watch

Deciding on the choice of watches is not easy, because now there are so many different types and shapes on sale with their own characteristics that your eyes begin to run wild. It is still easier for a man to make a choice based on his preferences, but a woman who wants to give a gift to a young man will need to carefully study his style and tastes so as not to make a mistake with the gift.

Mechanism

Much depends on which system controls the timekeeping: the energy independence of the watch, as well as the features of its style. Today, four types are most widespread:

1. Mechanical. Such an accessory can be reliably called a chronometer. The design is based on centuries of human experience in manufacturing high-precision mechanisms. The main element continues to be the watch spring, which requires regular winding. Such watches do not require additional energy sources to operate and are completely autonomous. With proper care, they can last for decades. When choosing a quality watch of this type, its owner can theoretically carry it all his life, and even pass it on to the younger generation.

   Mechanical wristwatch mechanism

2. Quartz. Electronics have replaced moving parts, gears and gears. This mechanism is based on a high-frequency generator with a quartz crystal, which supplies electrical impulses to a stepper motor. It requires very little current to operate, so these watches are powered by a tiny coin cell battery that lasts for a couple of years. The absence of the need for winding is combined in such watches with a classic pointer design. Such watches are usually cheaper than mechanical ones, although high-quality ones have a considerable price.

   Differences between quartz and mechanical watch movements

3. Electronic . The filling of these devices is a set of microcircuits, and time information is presented in digital form on an electronic display. Usually such watches have a certain style, opposite to the classic one. Ease of use coupled with wide functionality makes them significant competitors to their analogues.
4. Smart watch. They have become widespread recently, along with fashion and technological growth. They have a full-fledged software shell and are essentially more of a multifunctional device than a watch itself, so they will not be included in the review.

   Smart watch functions

Style

Style refers to the appearance of the watch, maintained in the same spirit. Traditionally, it is customary to distinguish between several basic styles, although sometimes specimens appear on sale that, as an experiment, combine the features of several styles.

1. Classic. Many mechanical watches are made in this style. Distinctive features are a round, less often rectangular shape with smooth contours, on the dial there are numbers or hour divisions with the numbers 12, 3, 6 and 9. The strap is usually leather or metal, the size is small, and the case is moderately thick. In the classics, emphasized execution of individual elements is not encouraged, for example, large crowns or a relief bezel. Everything in moderation is the main motto of this style. It is this category that includes the subspecies of “suit watches”—small, thin devices that are distinguished by their exquisite simplicity.

   Classic men's watches

2. Casual. Everyday watches may have a lot in common with classics, but they are not quite as formal. The main thing is ease of use. Subtly curved design, oversized elements for clarity, and a wide range of straps and attachments. The color and material of the case are not limited in any way. Most of the casual assortment consists of quartz dial watches of varying prices and quality.

   Casual men's watches

3. Sport. This category includes watches that are devoid of rigor and sophistication. Most models have a massive case with protruding buttons or crowns, wide straps or even bracelets that comfortably cover the wrists, large numbers and inscriptions. The standard among sports watches is their versatility. In addition to the hour dial, there may be stopwatches, date and time windows and other delights, for example, a built-in barometer or pedometer. Sometimes the arrows are duplicated with numbers on the electronic display. Such a watch is not suitable for a classic suit, as it simply will not fit under a shirt cuff. Many sports watches are equipped with shockproof mechanisms and water resistance.

   Sports men's watches

4. Original. Instances in which any characteristic feature acts as a dominant one. For example, skeleton watches have a transparent dial and caseback to show off the movement.

   Skeleton style men's watch

On a note! The bezel is the ring around the dial on which the numbers are printed. Many models rotate.

Housing material

Watch cases are most often made of metal. Plastic models can be either cheap or expensive, since the plastic used in them is not inferior in properties to metal. Usually electronic models are made with a plastic case - they are lightweight and not subject to corrosion. The most commonly used metals are:

1. Stainless steel. This is a durable metal with high performance characteristics. It is used in all styles, especially appreciated in models for extreme use.

   Stainless steel watch

2. Brass. A copper-based alloy that is softer than steel, but also does not oxidize under the influence of the environment and the human body. A watch with a brass case is durable enough to last for decades.

   Brass watch

3. Aluminum. Soft, but light metal. Watches made from it are cheaper, but in modern conditions this material can be easily given a wide variety of shapes and textures.

   Aluminum alloy watch

4. Titanium. A metal that has the lightness of aluminum but is stronger than steel. Rarely used and only in the most expensive watches.

   Titanium men's watch

Strap material

Today, there are several options for materials from which wrist straps for watches are made. Each of them is good in its own way, but also has its drawbacks.

1. Leather. The oldest option. The genuine leather strap looks expensive and stylish and is equipped with a clasp. An exclusive type of leather with embossing or an original pattern is used on premium devices, and you can also make such a strap yourself with minimal skills. Leather is soft and comfortable to wear on your hand, but over time this natural product wears out and gets worn out.

   Leather watch strap

2. Metal. A steel or brass bracelet is usually made to match the color of the watch case, so that the result is a single ensemble. Metal bracelets are strong and durable; the clasp usually wears out, and even then after many years. Most often, metal bracelets consist of links. The design of compression bracelets is interesting - they stretch when put on, and then contract, covering the owner’s hand.

   Metal watch strap

3. Rubber. There are natural and artificial rubber. In terms of performance, it is close to rubber. It is soft like leather, but does not rub or wear out as quickly. Artificial is more durable. It does not react with the skin, does not fade and fits snugly around the wrist.

   Rubber watch strap

4. Silicone. A polymer material, softer than rubber, it can be easily given a wide variety of shades. Durable but flexible. High wear resistance.

   Silicone watch strap

The best inexpensive wristwatches for men

An expensive watch is an excellent gift and has a long service life. However, not everyone has the opportunity to spend more than 10 thousand rubles on a chronometer. And some men just need a “workhorse” in order to keep track of time on shift. However, even budget watches today have a decent appearance and good functionality, not to mention ease of use.

No. 5. DIESEL DZ1437

Inexpensive watch with a stylish design. The steel case, like the dial, is painted matte black. To make the dial readable, the hands contain white markers. One head that adjusts the position of the hands. Standard quartz movement. The watch is well suited for young people and students who want to look stylish and at the same time cannot afford to buy a chronometer for 15-20 thousand rubles.

DIESEL DZ1437

Options:

• mechanism: quartz;
• time countdown: arrows;
• case material: steel;
• strap material: rubber.

• waterproof against splashes and light rain;
• stylish appearance;
• comfortable rubber strap;
• laconic execution;
• reasonable price.

Wristwatch DZ1437

A moderately priced watch from a fairly well-known manufacturer. They belong to the casual format: a comfortable leather strap is one-piece, not two parts, large heads for adjusting the hands of a stopwatch and a month and day indicator. They look more expensive than they cost, the quartz movement is almost flawless: in a couple of years the watch lag is less than a minute.

Source: https://obzor-expert.com/kak-vybrat-muzhskie-naruchnye-chasy-top-15-luchshih-modelej/