Nonmetallic inclusions

Metallic materials contain a class of non-metallic components. They are produced in the melting and solidification process of metals and alloys, and undergo a series of changes in the subsequent hot and cold processing process, which have many effects on the properties of metals and alloys.            According to the source of non-metallic inclusions, inclusions are usually divided into two categories: exogenous and endogenous. Refractory materials or slag particles mixed with metal (including those just brought in or having chemical reaction with liquid metal and having considerable changes in composition and structure) belong to foreign inclusions; in the process of smelting and solidification, the chemical reaction products of various chemical elements contained in the molten metal, which can not be excluded, remain in the solid metal, are called endogenous inclusions.            Chemical composition classification of inclusions:            ① simple oxide;            ② complex oxide;            ③ silicate and silicate glass            ④ sulfide            ⑤ nitride;