Vacuum hot pressing technology also has requirements for equipment

Vacuum hot press furnace can use graphite heating, molybdenum wire heating, periodic work, suitable for metal powder, inorganic non-metallic materials such as under vacuum, high temperature, hot press sintering, of course, can also be under the protection of the atmosphere for sintering. Thus completing the densification of the material, preventing deformation, but also has the effect of inhibiting the coarse grain size of the nano powder.

The process of hot pressing to compaction:

At the later stage of sintering, the pressure of closed pores increases, which cancels out the effect of surface tension and weakens the grain boundary diffusion, while the volume diffusion rate is slow, which makes the shrinkage difficult at the later stage. Hot pressing can provide an external force to compensate for the offset surface tension and promote sintering to continue.

Under the condition of hot pressing, the solid powder may exhibit the properties of non-Newtonian fluid. When the shear stress exceeds the yield point, the flow will occur, resulting in the increase of mass transfer speed, and the closed pores can be eliminated through the viscous or plastic flow of the material.

Requirements for Equipment:

1. The heating chamber can accommodate hot pressing components and molds.

2. Vacuum degree can meet the requirements of hot pressing process.

3, the temperature can be controlled and automatically adjusted, and the uniformity is good.

4, high pressure control precision, upper and lower pressure head in the center.

5, the press die material is high temperature resistant, can bear pressure, and does not react with the sintered body.

6, the equipment is safe and reliable, stable operation.

Article content from the network, if you have any questions please contact me to delete!