The sintering of tungsten carbide is a multiphase liquid phase process. During the sintering, the solubility of solid phase (refractory particles) should be limited in the liquid phase of the low melting point, so that the liquid phase will exist. It is important to study the solubility of solid phase in the liquid phase.

 

 

Main Impact Aspects:

1, It can improve wettability.

 

2, After the solid solution is dissolved in the liquid phase, the amount of liquid phase increases relatively. Increasing the volume fraction of the liquid phase can promote the densification.

 

3, As the change in the concentration of the solute leads to the difference in the surface tension of the liquid, material migration can be carried out, producing the liquid phase flow.

 

4, The components dissolved in the liquid phase can fill the surface defects of the solid particles and the clearance of particles, thus increasing the uniformity of the distribution of solid particles.

 

5, Protruding parts of the surface of the particles are preferred to dissolve. Through the diffusion and liquid phase flow in the particle sags, the morphology of the solid grain and the resistance to the rearrangement of the particles are improved.

 

6, The migration channel of solid material is increased, and the process is accelerated.

 

Dangers of Excessive Dissolution

1, Excessive solubility will lead to excessive liquid phases, which will do harm to the sintering process. For example, an alloy that forms an infinite intersoluble solid solution will be formed, making the liquid phase sintering cannot be carried out at all.

 

2, It is not appropriate to use liquid phase sintering if the solid solution has a bad effect on the performance of liquid phase (such as brittle).

 

3, High solubility results in the deformation of the sintered body and the conditions for grain growth.

 

4, The excessive dissolution of solid phase in the liquid phase leads to the orthogonality of the liquid phase and reduces the fluidity of the liquid phase.