Development trend of powder metallurgy special sintering technology

Oct 27, 2022

The special sintering technology of powder metallurgy is generally defined as that the green body or powder shrinks with time during the high temperature process; At a temperature lower than the melting point, the green body or powder becomes a dense polycrystal, and both the strength and hardness increase. This process is called sintering. Sintering, as the most important process in powder metallurgy production, has always been the focus of research on new materials in Dahong.

Qinhuangdao Zhongwei precisely found that in the process of high temperature, the batch consisting of metal or non-metallic raw materials may undergo a series of physical and chemical reactions, such as evaporation, dehydration, thermal decomposition, redox reaction and phase change; Co melting, melting and dissolution; Solid state reaction and sintering; Crystallization, crystal growth, residual glass phase solidification and cooling, etc. The main changes in sintering stage are the changes of particle or grain size and shape, and the changes of pore size and shape; At the final stage of sintering, the pores will be basically eliminated from the solid powder, forming a certain microstructure, thus giving it certain properties. Generally speaking, traditional sintering includes gas phase sintering, solid phase sintering, liquid phase sintering, reaction (instantaneous) liquid phase sintering, etc. Although some materials can be prepared by low temperature sol-gel, chemical vapor deposition (CVD) and physical vapor deposition (PVD), most materials still need high temperature sintering to achieve high density.

With the rapid development of materials science and technology, new types of special materials continue to appear. Common sintering methods, low temperature sintering under normal pressure, liquid phase sintering and additive assisted sintering have been difficult to meet the needs, so special sintering technology came into being. According to the sintering mechanism, characteristics and sintering means, metal powder injection molding manufacturers have developed special sintering technologies from traditional pressureless sintering, hot pressing sintering, liquid phase sintering, reactive sintering, etc. to hot isostatic pressing sintering, high-temperature self propagating combustion junction, ultra solidus liquid-phase sintering (SLPS), selective laser sintering (SLS), discharge plasma sintering (SPS), microwave sintering (WS), explosive sintering (ES), casting sintering (CST), electric field activated sintering (FAST) The production of these sintering technologies, such as atmospheric pressure consolidation (CAP), plays an important role in improving the performance of powder metallurgy materials, preparing special materials that are difficult to produce by conventional sintering methods, improving production efficiency and reducing costs.

To sum up, the MIM technology experts found that at present, the powder metallurgy special sintering technology is developing towards the direction of high density, high performance, high efficiency, energy saving and environmental protection, and new special sintering technology is being continuously developed and applied. For more information about metal powder injection molding technology, please consult the MIM technical team of Zhongwei Precision Metal Powder Injection Molding in Qinhuangdao!