Surface Treatment Process Of Powder Metallurgical Parts

In order to improve the wear resistance, corrosion resistance, and fatigue strength of powder metallurgy parts, surface treatment is required to make their surfaces more functional and compact. So, what is the surface treatment process for powder metallurgy parts?
The surface treatment process of powder metallurgy parts can be basically divided into the following five categories:
1. Coating: Cover the surface of the processed part with a layer of other materials without any chemical reaction;
2. Surface chemical treatment: The chemical reaction between the surface of the treated part and the external reactant;
3. Chemical heat treatment: Other elements such as C and N diffuse to the surface of the treated part;
4. Surface heat treatment: Phase transformation occurs through cyclic changes in temperature, causing changes in the microstructure of the surface of the treated piece;
5. Mechanical deformation method: causes mechanical deformation on the surface of the treated part, mainly to generate compressive residual stress while also increasing the surface density.
The above is about the surface treatment process of powder metallurgy parts. In principle, all surface treatment processes applied to dense steel products can be used for iron-based powder metallurgy materials, but there are two prerequisites that must be considered. The first is to maintain precise dimensional tolerances that have the advantage of strong competitiveness as powder metallurgy parts after treatment. If the surface treatment process used deprives powder metallurgy parts of this advantage, it cannot be applied. Secondly, due to the presence of pores in powder metallurgy parts, this will have a significant impact on some existing surface treatments.