Hadfield steel characteristic: composition, application

The metallurgical industry is one of the most important components of each country's GDP, and it also produces unique and useful materials. Humanity could not do without the products produced by metallurgical plants. Steel is one of them. There are different types of this material that are used in many industries. Steel, which has a high ductility and degree of wear, it is - Hadfield steel - a unique alloy. The requirements for it are regulated by GOST 977-88 and foreign analogues (USA, England, Germany, China, Japan, Finland, Spain, Korea).

Hadfield Steel History

Based on the name, it can be argued that it was Robert Hadfield who received this alloy. Who was this developer? Robert Hadfield is an English metallurgist who obtained an alloy with increased strength in 1882. Quickly enough, this steel became widespread and turned out to be a very unique material.

After Hadfield developed a unique steel, the military became interested in its development. This is not surprising, since such an alloy is an integral component for creating protective equipment for the military.

The ruggedized infantry helmets are the first protective gear based on Hadfield steel. Similar helmets were used by soldiers of the British army, then the US military became interested in the development and began their production. Until the 80s, Hadfield's steel technology did not change. But since the 80s, organoplastics was developed, which was not inferior in strength to the material developed by the British metallurgist, but was much lighter.

Helmets for infantry are not the only use of Hadfield steel. The British company Vickers was the first to use this stainless steel for other purposes. Caterpillar tank tract began to produce from the Hadfield alloy in the 20s. Steel increased the mileage of tank tracks from 500 to 4,800 kilometers. During World War I, such an increase in mileage was considered almost a miracle. Hadfield steel has become indispensable for tank building. Soon this alloy was used not only in tank building, but also in other industries. In the USSR, Hadfield steel began to be smelted in 1936.

Hadfield Steel: Composition

Analyzing the chemical composition, especially the percentage of carbon and manganese, we can see that it is austenitic steel. Such a structure increases wear resistance and strengthens the alloy. Thus, steel is resistant to deformation processes, having a high degree of ductility and toughness. Metallurgists say this alloy was the first alloy steel to be mass-produced.

Hadfield Steel Properties

Due to its properties, austenitic steel could not be processed with cutting tools, as it has a high viscosity. For the manufacture of products from this material, only casting may be suitable.

Hadfield alloy has a high hardening ability, which is significantly higher than that of similar steel alloys. Austenitic steel has low hardness, but also high wear resistance under shock, high pressure and temperature changes. Based on these characteristics, we can say that the steel of the British metallurgist is suitable for work in aggressive environments.

Hadfield Steel Welding Technology Features

The thermal conductivity of austenite is significantly lower than that of other steels, 4-6 times. The coefficient of thermal expansion is several times greater than that of mild steels - 1.9 times. These are very important characteristics of the metal, as it affects the possibility of the occurrence of cold cracks in the temperature range.

There is a significant likelihood of hot cracks, which is associated with foundry shrinkage of the alloy, which is 1.6 times more than low-carbon metal. High temperature transforms the austenitic structure into a martensitic one, which increases the risk of cracks in the area affected by high temperatures.

Hadfield Steel Applications

Due to its chemical composition, characteristics and characteristics, austenite is used in many industries. Using steel products, you can be sure of their reliability and highest strength.

Wear-resistant steel is a fairly popular material. A huge number of industrial enterprises that produce high-strength products use Hadfield steel. The following products are made from this alloy:

• Engineering products.
• Truck tracks of tanks.
• Tractors
• Railway crosses.
• Turnouts capable of operating under severe shock loads and abrasion conditions.
• Prison bars on the windows.
• Components of crushers.

It is interesting to make prison bars from austenite. Many believe that this is a form of mockery of prisoners who are trying to escape. According to the classics of the genre, many relatives carry hacksaws for prisoners, who, in the hope of freedom, begin to cut window grills.

In the case of using ordinary metal, there is a chance of escape. But the Hadfield alloy is a wear-resistant steel that cannot be cut with an ordinary hacksaw. If you start to saw gratings from the Hadfield alloy, then the surface hardening begins, which entails the hardening of austenite. The hacksaw increases the lattice hardness to a hacksaw hardness and higher. Therefore, we can talk about the unreality of the escape.

Steel 110G13L

Steel grade 110G13L is alloyed, which is used for castings and has special properties. This steel has high abrasion resistance to impact or pressure drops.

Application of steel grade 110G13L

This steel grade is used in the production of the following materials:

• Heavily loaded parts that must be wear resistant.
• Cone Crusher.
• Teeth, walls of excavators.
• Case of ball, vortex mills.
  

Steel grade analogs

Many countries produce such steel.

Properties of steel grade 110G13L

Technological and mechanical properties of the material are given in the tables.

Mechanical properties at = 20 ^o steel grade 11013

Heat treatment

The heat treatment of Hadfield steel directly depends on the level of carbon content in the alloy. The higher the carbon level, the higher the temperature should be. For example, if in the alloy it is at the level of 1%, then the temperature should not be lower than 900 degrees. If carbon is 1.5%, then processing is possible at 1000 degrees. If carbon is at a level of 1.6% in the alloy, then the temperature should be above 1050 degrees. This is followed by water cooling.

High temperature is necessary for the complete dissolution of carbides that degrade the quality of the casting, and for the growth of austenitic grains. The exposure time of the casting depends on its thickness. So, a thickness of 30 millimeters requires an exposure of 4 hours, and 125 millimeters - in 24 hours.

The wear resistance of Hadfield steel in the cast state is the same as after quenching. The austenite structure is surrounded by a carbide network and behaves under wear conditions in the same way as a uniform hardened alloy. That is why it can be argued that cast austenite in some microvolumes has the same viscosity and wear resistance as hardened steel. Its increased fragility is explained by the influence of the carbide network, which causes a strong concentration of internal stresses.

Hadfield Steel was developed several decades ago. Today, alloy steel is an integral part of the production of many goods in various industries. Without it, industries such as engineering, oil and gas, chemical, food, energy industries could not function normally. Do not forget about the construction, tank building and development of new types of weapons that use the new achievements of the metallurgical industry. However, engineers and metallurgists do not fully understand all the properties, features and characteristics of alloy steels.