Factors influencing the sintering quality of metal powder injection molding (MIM)

Many factors that affect the properties of a sintered body, that is, the properties of the powder, molding and sintering conditions. Factors of sintering conditions include heating rate, sintering temperature and time, cooling rate, sintering atmosphere and pressure conditions.

The temperature and time of sintering can affect the porosity, density, strength and hardness of sintered body. High sintering temperature and long heating time will reduce product performance and even lead to product burning defects. Meanwhile, low sintering temperature or long heating time may cause performance degradation due to sintering process.

Sintering atmosphere is usually used for injection molding of metal powder. The sintering atmosphere directly affects the properties of the sintered body. Sintering in a reducing atmosphere prevents the burning of the compact and allows the reduction of surface oxides. For example, iron and copper based products usually use gas or ammonia decomposition, while hard alloys and stainless steel usually use pure hydrogen. Active or refractory metals (e.g. Beryllium, titanium, zirconium, tantalum), carbide containing Tic alloy and stainless steel can be used for vacuum sintering. Vacuum sintering can avoid harmful components (H2O,O2). If there are two or more components in powder compaction, sintering may occur on the melting point of the components, resulting in a small amount of liquid phase in powder compaction.

Pressure sintering exerts pressure on the powder during sintering to promote the densification process. Sometimes pressure sintering and hot pressing are synonymous, but hot pressing refers to the process of directly obtaining products after powder molding and sintering.

Activation sintering simultaneously improves the properties of the sintering body and also adopts some physical or chemical measures to significantly lower the sintering temperature and reduce the sintering time. Activated sintering when the powder is introduced into the compaction process, through DC (DC) and pulse power, then an arc is generated between the powder particles. Then the sintering process begins. In the process of sintering, pressure is gradually added to the workpiece to combine the forming and sintering of the two processes.

The above is a brief explanation of the influence factors on the sintering quality of metal powder injection molding (MIM) from guangdong dahong new material. Does it help you understand the technology of metal powder injection molding (MIM)? More about metal powder injection molding technology related content, welcome to consult guangdong da-hong new material metal powder injection molding MIM technical professional team to answer for you!