（Is the drying of green body important?）
Is the drying of green body important?
The drying of green body is an important process step in many fields, such as powder metallurgy, industrial ceramics and refractory materials. The residual moisture in the green body will affect the physical or mechanical properties of the sintered body, reduce shrinkage during sintering, increase the porosity after sintering, and seriously affect the accuracy, quality and performance of parts. The green body must be dried before sintering in order to reduce the water content to below a certain value.
The role of drying green body is mainly reflected in two aspects. First, the drying process can effectively reduce the moisture content of the green body, and then reduce the steam pressure generated during sintering to reduce the pore rate of the sintered body. Secondly, drying can reduce the water diffusion coefficient and the self-diffusion coefficient, so that the pore size and uniformity of sintered body are more uniform.
In order to obtain an ideal sintered product from a green body, it is necessary to effectively control the residual moisture in the body. The key is to grasp the drying process parameters and improve the drying efficiency. The drying parameters include temperature, drying time and drying effect. Generally, when the drying time is short and the temperature is low, the drying effect is not good, and the drying efficiency needs to be improved.
In short, the drying of green body is very important. Improper drying process will cause a series of issues, such as cracking, expansion, decreased-density and distortion after sintering. It is necessary to ensure that the green body is dried to a certain moisture content before sintering. Control of drying parameters and improvement of drying efficiency will make a huge difference in the drying quality.
