The blowhole of die casting is widely existed in castings. How to solve the blowhole defect is a headache for many manufacturers. Because of the blowhole, many castings with pressure requirements have to be scrapped, resulting in the waste of production cost. Infiltration is widely used in automobile industry, gas and hydraulic industry, pressure components manufacturing, powder metallurgy industry and other industries. The excellent infiltration process can not only save the cost of poor quality, but also meet the requirements of temperature resistance, vibration resistance and sealing performance, but also further improve the compactness and aging of castings. Infiltration is the best solution to solve the problem of air holes in castings and it is the best way to save cost. With the higher requirements of environmental protection and quality in the world, infiltration is not only a temporary plugging of unqualified products, but also a guarantee of quality. In developed countries, infiltration has become a necessary process; in China, more and more attention has been paid to infiltration.