Superalloy refers to a class of metal materials based on iron, nickel and cobalt, which can work for a long time at a high temperature above 600 ° C and under certain stress. It also has excellent high temperature strength, good oxidation resistance and thermal corrosion resistance, apart from good fatigue properties, fracture toughness and other comprehensive properties. They are also known as "super alloys" which are mainly used in aerospace and energy fields.