Metal injection molding (MIM) solutions
Production process and application of metal injection molding (MIM)
MIM manufacturing process generally includes: mixing granulation, injection molding, degreasing, sintering and secondary treatment.
(1) Main technical features of MIM process:
1. It is suitable for the forming of various powder materials, and the products are widely used;
2. With high utilization rate of raw materials and high degree of production automation, it is suitable for continuous mass production.
3. It can directly form small parts with complex geometry (0.03g ~ 200g);
4. High dimensional accuracy (± 0.1% ～ ± 0.5%) and good surface finish (roughness 1 ~ 5 μ m）；
5. The product has high relative density (95 ~ 100%), uniform structure and excellent performance;
(2) Several common surface treatment processes of MIM parts
Using mechanical, chemical or electrochemical action to reduce the surface roughness of the workpiece, so as to obtain a bright and flat surface.
The process of attaching a layer of metal film to the surface of metal or other material parts by electrolysis. Electroplating can prevent metal oxidation (such as corrosion), improve wear resistance, conductivity, reflection, corrosion resistance (copper sulfate, etc.) and enhance beauty.
The process of using physical process to realize material transfer and transfer atoms or molecules from source to substrate surface. Its function is to spray some particles with special properties (high strength, wear resistance, heat dissipation, corrosion resistance, etc.) on the matrix with lower performance, so that the matrix has better performance.
It is a common chemical treatment method to produce a layer of oxide film on the metal surface to isolate the air and achieve the purpose of rust prevention. Blackening treatment can be adopted when the appearance requirements are not high. The main components of blackening liquid are sodium hydroxide and sodium nitrite.
It is a process of chemical and electrochemical reaction to form phosphate film. The main purposes of phosphating are:
1) Provide protection for the base metal and prevent the metal from being corroded to a certain extent;
2) It is used for priming before painting to improve the adhesion and anti-corrosion ability of the paint film.