In order to evaluate the feasibility of the application of thin Al-Si coated hot formed steel in automobile body, hot stamping test, spot welding test, adhesive matching test and coating test and corrosion resistance test are carried out on single-sided Al-Si coated materials with the weight of 20 g/m² (AS20) and 75 g/m² (AS75). The results show that: AS20 material can use the same heating temperature as the AS75 material, but the heating time is less than the AS75 material; under the optimal heating process, the mechanical properties of the two materials are comparable; the ultimate sharp cold bending angle and maximum force of the AS20 material are higher than those of the AS75 material; the shear strengths of the adhesive joints between the two materials and the structural adhesive currently used in production are comparable, the AS20 material matches well with the structural adhesive currently used in production; the peeling diameter of the fully damaged welding point and the fusion diameter and failure mode of the welding assembly where the two materials are located are equivalent, the spot weldability of the AS20 material is equivalent to that of the AS75 material; the adhesion and corrosion resistance of the electrophoretic paint film of the two materials are comparable. Overall, based on multi-performance comparative evaluation analysis, the main application properties of thin aluminum silicon coated hot formed steel meets the using requirements of OEMs.

Al-Si coating  /  Hot-formed steel  /  Heating process  /  Spot welding quality  /  Corrosion resistance