DP980+Z烘烤硬化值与退火温度的关系

为了研究退火温度对镀锌DP980+Z烘烤硬化值的影响,退火温度控制在760～820℃之间,系统分析退火温度对烘烤硬化值的影响。通过准静态拉伸试验机测量烘烤硬化值及抗拉强度,采用lepara试剂对组织中的马氏体进行着色,利用金相显微镜及图像处理软件测量马氏体的体积分数;采用扫描电镜观察DP980+Z的双相组织特点,并且将组织图片通过CAD转化成有限元图进行网格划分,建立代表性体积单元(RVE),通过有限元分析铁素体、马氏体强度对烘烤硬化值的影响。在同样的变形量情况下,DP980+Z的原始屈服强度越高,烘烤硬化值越高。

Correlation between bake hardening values and annealing temperature of DP980+Z

The annealing temperature was controlled in the range of 760 to 820℃ to investigate the effect of annealing temperature on the bake hardening (BH) value of DP980 + Z. The tensile strength and BH values were tested by quasi static tensile testing machine. Martensite was colored by Lepara reagent and its volume fraction was measured by color metallography. The dual phase microstructure of DP980+Z was observed by scanning electron microscopy, and the results were analyzed by finite element analysis using CAD. Representative volume element (RVE) was built to investigate the effect of tensile strength of ferrite and martensite on BH values. Results demonstrate that under the same deformation amount, the higher original yield strength of DP980+Z leads to the larger bake hardening value.