滚轮滚挤压过程的有限元建模与分析

Finite Element Modeling and Analysis of Roller Burnishing Process

在试验研究的基础上,通过非线性有限元软件MSC.Marc采用Johnson-Cook流动应力模型对滚轮滚挤压45号钢进行了二维有限元数值模拟,从微观角度了解滚轮滚挤压变形机理并得出在特定条件下滚轮滚挤压后工件表面的残余应力分布;从车削残余应力的角度分析了车削加工对滚挤压效果的影响。模拟结果表明工件最表层的车削拉伸残余应力在滚挤压后转变成了高数值压缩残余应力,它延缓了零件表层疲劳裂纹的萌生和扩展,说明滚挤压过程能极大地改善零件性能。

Based on experimental research, two-dimensional model of roller burnishing process was developed using non-linear finite element code MSC. Marc, in which Johnson-Cook flow stress material model was used. It helps in fundamental understanding of the burnishing process mechanics. The magnitude and distribution of the residual stress obtained by the finite element analysis under a specific condition was used to analyze the influence of the initial turning process on the burnishing effects on the aspect of the residual stress produced by turning. Turning residual tensile stress at the outermost surface after turning is replaced by residual compressive stress after burnishing. This process delays fatigue crack nucleation and propagation occurs at surface, which can improve the functional properties of part a lot.