Use of the raw materials of stamping parts, must be in accordance with GB 710-65 "quality carbon steel thin plate technology conditions", GB 2517-81 the general structure of strip steel and steel belt, GB 2521-81 cold rolled electrical steel belt and other regulations on metal material standard, and conform to the supply status of material or other requirements. Stamping certificate should have the quality of raw materials, it guarantees material conform to the provisions of the technical requirements. When there is no certificate of quality or for other reasons, stamping parts factory to conduct re-inspection according to need to select raw materials. Appearance inspection: the inspection material surface defects, stain, outer profile dimension, shape and thickness and table sigma surface roughness. Chemical analysis, metallographic examination, content of chemical element in the analysis of materials; Determine level of material grain size and uniformity; Evaluation materials free cementite, banded structure and nonmetallic inclusions level; Check the material defects such as shrinkage cavity, porosity. Material mechanical performance test of tensile strength, yield strength, sigma sigma b s showed sigma s/sigma, elongation delta, reduction of area b bits and rockwell hardness HRB, etc. Forming performance test, bending test, cupping test was carried out on the material, the determination of material strain hardening index n value and plastic strain ratio r value, etc. About steel sheet formability test method, according to the provisions of the sheet metal forming performance and test methods. Other performance measurement: the electromagnetic properties of the materials and the determination of coating, coating adhesion ability, etc.