Damage Evolution of Antibacterial Stainless Steel at Different Loading Rates Based on Digital Image Correlation Method

Using Shimadzu AGS-100KN tensile machine, LEICA-LM/DM optical microscope, and electron backscatter diffractometer (EBSD), combined with digital image correlation (DIC) analysis method, the damage evolution behavior of copper-containing antibacterial stainless steel in large deformation area and small deformation area under different loading rates is investigated. The results show that with the increase of the loading rate, the temperature rise induces local adiabatic shear bands in the microstructure, increasing work hardening, and a decrease in ultimate stress and full elongation. The damage evolves in the large deformation area, the sample is mainly deformed rapidly, the grain deformation degree is large, and the deformation basically stops in the small deformation area. The damage factor of the specimens in the large deformation zone and the small deformation zone increases with the increase of strain, and the damage deformation rate and the critical damage factor decrease with the increase of the loading rate. Based on the DIC method, the damage evolution equations of copper-containing antibacterial stainless steel samples in large and small deformation regions under different loading rates are established, which effectively reflect the damage evolution laws at different loading rates.