Introduces the process characteristics and basic process flow of powder metallurgy

Powder metallurgy is the process technology of making metal or metal powder (or the mixture of metal powder and non-metal powder) as raw material, through forming and sintering, making metal materials, composite materials and various types of products.The broad powder metallurgy products industry includes iron and stone tools, hard alloy, magnetic materials and powder metallurgy products.In the narrow sense, P/M products only refer to P/M products, including P/M parts (accounting for the majority), oil bearing and metal injection molding products.
Process characteristics:
1, the product density is controllable, such as porous materials, good density materials, etc.
2, fine grain, uniform microstructure, no component segregation;
3, near forming, raw material utilization rate > 95%;
4, less no cutting, cutting processing is only 40~50%;
5, the material component is controllable, conducive to the preparation of composite materials;
6. Preparation of insoluble metals, ceramic materials and nuclear materials.
Basic process flow:
1. Pulverizing is the process of making raw materials into powder. The commonly used pulverizing methods are oxide reduction method and mechanical method.
2. Mixing Mixing is a process of mixing all kinds of required powder in a certain proportion and homogenizing it into billet powder.There are three kinds of dry type, semi-dry type and wet type, which are used for different requirements.
3. Forming is a process in which the mixture is evenly mixed and loaded into a pressing die to be made into a blank with a certain shape, size and density.The molding method is basically divided into pressure molding and non – pressure molding.Pressure molding is the most widely used molding.
4, sintering sintering is a key process in powder metallurgy process.The final physical and mechanical properties are obtained by sintering the compacted blank after forming.Sintering is divided into unit sintering and multi – component sintering.In addition to ordinary sintering, there are loose sintering, melt leaching method, hot pressing method and other special sintering processes.
5, after the treatment of sintering, according to the different requirements of the product, can take a variety of ways.Such as finishing, immersion, machining, heat treatment and electroplating.In addition, in recent years, some new processes such as rolling and forging have also been applied to the processing of powder metallurgy materials after sintering, and achieved better results

Post time: Apr-13-2021