Powder metallurgy injection molding technology is developing rapidly although it is not yet fully mature. We all know that the basic process of powder metallurgy has several steps, and today we will explain the sintering process of defective blocks. Sintering is a very critical process in the powder metallurgy process, so let's take a closer look at this process.
For unit cell and multi-component solid-phase sintering, the sintering temperature is lower than the melting point of the metal and alloy used. For multi-component liquid-phase sintering, the sintering temperature is generally lower than the melting point of the difficult-to-melt component but higher than the melting point of the easy-to-melt component. In addition to ordinary sintering, there are special sintering processes such as loose sintering, melt immersion, and hot pressing.
People have long used this process to produce ceramics, powder metallurgy, refractory materials, ultra-high temperature materials, etc. Generally, after the powder is shaped, the dense body obtained by sintering is a polycrystalline material, and its microstructure is composed of crystals, glass bodies, and air holes. The sintering process directly affects the grain size, pore size, and grain boundary shape and distribution in the microstructure. The properties of inorganic materials are closely related not only to the material composition (chemical composition and mineral composition) but also to the microstructure of the material.
Controlling the gas phase pressure in the sintering process is very important, especially when the system studied contains variable valence ions, the gas phase pressure of the solid-state reaction will directly affect the composition and structure of the product. For example, in the synthesis of copper oxide high-temperature superconductors, the sintering process must strictly control the oxygen partial pressure to ensure that the superconducting material with a determined structure, composition, and copper valence state distribution is obtained.
In the preparation of inorganic solid compounds using solid-state reactions, the reaction rate is controlled by the diffusion process, and often requires high temperatures to make the reaction effective. In addition, some solid compounds are composed of solid-liquid phases, and will undergo decomposition reactions when melted, so the powder injection molding process sintering should generally be carried out below the product's melting point to ensure uniform phase formation. However, the sintering temperature cannot be too low, otherwise, the reaction rate of the solid-state reaction will be too low.
Above is the process of sintering in the powder metallurgy process and a summary of sintering and its production process. JINLONGYUAN, the first brand manufacturer of powder metallurgy injection molding, is your best choice. If you need it, please feel free to contact us!