The raw materials used for forging are ingots, rolled materials, extruded materials and forging blanks. Rolled materials, extruded materials and forging billets are semi-finished products processed by rolling, extruding and forging of ingots respectively. Under normal circumstances, the occurrence of internal defects or surface defects in ingots is sometimes inevitable. For example, internal composition and tissue segregation, etc. Various defects in raw materials will not only affect the forming of forgings, but also affect the final quality of forgings. Therefore, quality control of raw materials must not be ignored.
