Die casting is a special casting process. Compared with other casting processes, die casting process is basically characterized by the filling up and shaping of die casting mould with liquid metal under high speed and pressure conditions. Injection during mould filling process and fast cooling of metal moulds are detrimental to the forming of die casting moulds, resulting in many defects of die castings. Some defects are inevitable, but others can be avoided. Some defects have no effect on properties of die castings, so such die castings can still be used. However, some defects affect properties of die castings, and such die castings should be disposed of as wastes.
Thus, quality is the lifeblood of enterprises, an important pillar of enhancing enterprises' competitiveness as well as an important condition of increasing economic benefits. Therefore, improving the quality of die castings is advantageous for enterprises to increase economic benefits or reduce waste of resources.
Besides, there are several indirect reasons for causing defects, including imperfect management like poor on-site quality management, and malpractice or irresponsibility of operators and so on.