Warm compaction has great advantages in manufacturing low cost, high density, high strength, high precision and complicated complex parts. As a result, it has a broad application prospect in the preparation of tungsten carbide. 

 

The key technology of this technology is the preparation of the powder for temperature and pressure, the selection, combination or modification of the new lubricant, and the development of the temperature and pressure system.

 

 

1, Preparation of Powder Raw Materials for Warm Compaction

Requirements for the mixed powder for warm compaction should not only have good compressibility, fluidity, and consistent bulk density not only in the process of heating, transmission and pressing. And the performance consistency between the parts made should also be good. The suitable powder material should be as follows:

1.1, Suitable granularity of the base powder should have enough space for the rearrangement of the particles, which is beneficial to the high filling density.

1.2, Spherical powder particles have the smallest surface area, which can reduce the rearranged resistance.

 

2, Selection of polymer additives

The primary task in developing the new warm compaction technology is to select or develop a suitable polymer additive, which can be used as a binder/lubricant. The effect of lubricant is to reduce the friction between the powder, reduce the rearrangement resistance of the pressing process and increase the compaction density. It plays an important role in improving the density of powder metallurgy parts. The pressing temperature should be controlled within a certain range, in which the selected lubricant has the best lubrication effect. At the same time, the lubricating film formed by the binder and lubricant is more easily destroyed as the temperature rises too much. 

 

3, Powder heating system and mould heating device

At present, the heating systems of warm compaction are the resistance heating, the microwave heating, the infrared heating and the hot oil heating. This requires the formation has a certain strength.

 

4, Requirement for Mold Unloading

The body formed after forming slurry should be easy demoulding.

 

5, Requirement for Bubble

It requires as little as bubbles in the mud.