The pressing molding in powder metallurgy is to use gravity to fill powder material in rigid mold cavity, and punch to form pressure. In order to reduce metal loss in the subsequent processing of metal products, the size accuracy and density uniformity of the product should be controlled as far as possible in the forming process, which requires the high precision of the molding equipment and the molding mold. Under the condition that the tonnage of the press is sufficient, the mold design should be improved to improve the efficiency of pressing molding.

 

 

In the precision compaction of tungsten carbide mold powder, the requirement of mould should be considered in the following aspects:

 

1, Mold cavity should have high hardness and high strength. Because of the high hardness of the tungsten carbide particles, it has a great scratch and damage to the mold cavity, which is easy to cause the waste of the mould and makes the production cost increase sharply. High hardness forming surface of the die can effectively improve the service life of the mould and reduce the production cost. When the areas are same, the mold wall of the porous mold is thinner than the ordinary single hole die wall. In order to ensure the service life of the mould, the mold cavity material has higher strength.

 

2, High precision coordination of the die and punch is required as the size deviation of each cavity will accumulate and increase the overall deviation. This requires that the basic dimension accuracy and shape position of mold should be controlled in 0.01mm.

 

3, For the small products of tungsten carbide die, measures should be taken to improve the molding efficiency and reduce the cost of molding in the mold design and molding way because of the small single weight and high cost of single branch molding.