Microstructure Evolution Analysis of 302HQA Stainless Steel during the Cold Forming Process

The cold deformation behavior of 302HQA stainless steel was systematically investigated through compress tests at room temperature. By means of microstructure and X-ray diffraction analysis, deformation-induced martensite transformation (DIMT) was found in this alloy during the cold forming process. The result of magnetic measurement shows that the amount of deformation-induced martensite increases with the increasing of plastic strain. When the plastic strain is lower than 30%, the amount of martensite increases with the increasing of strain rate, while the plastic strain is up to 50%, the amount of deformation-induced martensite decreases with the increasing of strain rate due to the effect of deformation-induced heat accumulation.