What will the heat treatment of powder metallurgy gear materials be affected by?

What will the heat treatment of powder metallurgy gear materials be affected by?

What will the heat treatment of powder metallurgy gear materials be affected by? A kind of air hole will be formed in the sintering process of P/M parts, which will have a certain impact on the heat treatment process of P/M parts. In order to improve the precision and grain size of the alloy, the increase of alloy elements will also have an impact on the heat treatment. So, what influence will the heat treatment of powder metallurgy gear materials be affected? Zhongwei Precision Powder Metallurgy Parts Processing Factory shares:

1. Effect of porosity on heat treatment depth

   
   

The heat treatment effect of powder metallurgy materials is related to the density, permeability (hardenability), thermal conductivity and electrical resistance of the materials. The porosity is the biggest cause of these factors. When the porosity exceeds 8%, the gas will rapidly penetrate through the pores. When carburizing and hardening, the effect of surface hardening will be reduced by increasing the carburizing depth. Moreover, if the carburizing gas penetrates too fast, soft spots will be produced during quenching, which will reduce the surface hardness and make the material brittle and deformed.

Powder metallurgy gear

2. Effect of porosity on heat treatment process

During the heat treatment of powder metallurgy materials, the rapid cooling can inhibit the diffusion of austenite into other structures, so as to obtain martensite. The existence of pores has a great impact on the heat dissipation of materials.

3. Effect of Alloy Content and Type on Heat Treatment

Copper and nickel are common alloy elements, and their content and type will affect the heat treatment effect. The hardening depth of heat treatment increases with the increase of copper content and carbon content, and decreases when it reaches a certain content; The stiffness of nickel alloy is higher than that of copper alloy, but the inhomogeneity of nickel content will lead to the inhomogeneity of austenite structure.

4. Effect of High Temperature Sintering

Although high temperature sintering can obtain the best alloying effect and promote densification, different sintering temperatures, especially at low temperatures, will lead to a decrease in heat treatment sensitivity (alloy in solid solution decreases) and mechanical properties. Therefore, good heat treatment effect can be obtained by using high temperature sintering with sufficient reduction atmosphere.

The above points are Zhongwei's introduction to the factors that will affect the heat treatment of powder metallurgy gear materials. After reading these contents, do you know what will affect the heat treatment of powder metallurgy gear materials? If you have any questions or needs related to powder metallurgy gears, please call Zhongwei Precision.