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The elements in wear-resistant alloy steel have a great influence on the tempering, processing and cutting performance in the later stage. If the residual elements are too much, it will also affect the quality of wear-resistant alloy steel castings. How should steel casting manufacturers control these elements, and what effect do these elements have on the casting itself?

1. Effect on weldability and workability of steel:

Manufacturers of steel castings wish to measure the technological properties of steel. Weldability and workability are the main aspects to check this. All alloying elements that can improve hardenability ignore the weldability of steel, because when cooling on the side of the welding heat-affected zone near the fusion line, it is easy to form hard and brittle structures, such as martensite, on the other hand, this may Cause cracking, due to high temperature, the grains near the fusion line in the heat-affected zone are easy to become rough, so the elements contained in wear-resistant alloy steel that can refine the grains, such as titanium and vanadium, is beneficial.

Steel casting manufacturers can improve the workability of steel by adding appropriate amounts of sulfur, lead and other elements to the steel. The alloy elements in wear-resistant alloy steel usually increase the hardness of the steel, so it will increase the cutting resistance and increase the wear of the tool. The workability of steel is affected by the matrix structure of the steel, the type, shape and number of inclusions.

2. The influence on the mechanical properties and tempering properties of steel:

The properties of steel mainly depend on the properties of iron solid solution and carbide and their relative distribution. The effect of alloying elements on the mechanical properties of steel is also closely related to this. The alloying elements dissolved in ferrite will play a solid solution strengthening role, improve the hardness and strength of steel, but also reduce the toughness and plasticity of steel.

The ductile-brittle transition temperature of the steel cast is an important index to evaluate its mechanical properties.

(1) The elements that can reduce the transition temperature are nickel and manganese.

(2) Elements that can increase the transformation temperature include boron, silicon, molybdenum, copper, chromium, etc.

(3) The AI element will reduce the transition temperature by a small amount and increase the transition temperature by a large amount.

(4) Ti and V elements can increase the transition temperature by a small amount and reduce the transition temperature by a large amount.

The tempering stability of wear-resistant alloy steel is better than that of carbon steel, because the alloy elements hinder the diffusion of atoms in the steel during tempering. Therefore, at the same temperature, it can delay the decomposition of martensite and resist tempering softening. In addition, the carbide-forming elements also play a very significant role in retarding temper softening. Although cobalt and silicon are non-carbide forming elements, they have a strong delaying effect on the movement and growth of cementite nuclei. Therefore, they also have the effect of retarding tempering softening.

The performance characteristics of wear-resistant alloy steel:

(1) Ordinary low-alloy structural steel Although ordinary low-alloy structural steel is a low-carbon (C<0.20%) and low-alloy (total alloy element content <3%) steel, due to the strengthening effect of alloy elements, and carbon Compared with the same carbon structural steel, this steel has higher strength (especially yield point), and has good plasticity, toughness, corrosion resistance and weldability.

(2) stainless steel Stainless steel is the general term for stainless steel and acid-resistant steel that is resistant to atmospheric, acid, alkali and salt corrosion. Generally speaking, steel that can resist corrosion in the atmosphere is called stainless steel. Steel that can resist corrosion in strong corrosive media is called acid-resistant steel.