The dry pressing mould for porcelain powder is mosaic structure, of which the working part is made of common tungsten carbide material. After testing and selecting, YG15 and YG8 tungsten carbide were used as material, avoiding the shortcomings of the mosaic structure. 

 

However, because of the low flexural strength and impact toughness of the tungsten carbide, the large brittleness and the folding phenomenon during the forming process that causes the die to collapse and fracture, the normal production is affected, increasing the production cost. Therefore, it is necessary to choose new materials and new grinding processes to ensure product quality and normal production.

 

 

Initial material of the upper and lower die is YG15 while the concave die sleeve (middle work part) is YG8. Because of the high hardness of tungsten carbide, grinding is time-consuming and laborious. If the die is cracked, it will be completely scrapped if it breaks larger or breaks. However, steel bonded tungsten carbide has good cutting performance, though of which the wear resistance is not as high as YG15 and YG8. And because of good toughness, its microstructure can be improved, and grain can be refined through heat treatment. 

 

During the traditional grinding process, the grinding force is high, the grinding temperature is high, and the grinding efficiency is low. At the same time, the grinding wheel is very easy to passivate and clog and lose the cutting performance, which causes brittle failure and stress concentration, deteriorating the processing quality and making it difficult to meet the high precision and high efficiency processing requirements. For working surface of the mold, the ELID precision mirror grinding technology can be applied to the mold surface so as to achieve the product quality requirements.

 

Heat treatment of steel bonded tungsten carbide can improve internal structure and improve its macro mechanical properties. Using the precision mirror grinding technology for on-line electrolytic repair to grinding the mould table instead of the original traditional grinding process, it can ensure the quality of the product and improve the efficiency and ensure the smooth production of the production.