摘要
基于Johnson-Cook方程建立超声冲击处理的三维有限元模型,研究超声冲击处理奥氏体不锈钢S30408的动力学过程,分析覆盖率、搭接率、冲击次数对表层残余应力分布、塑性变形及形貌的影响。结果表明,覆盖率的增加提高了冲击处理后材料表面的压应力值,同时降低了冲击坑边缘的最大拉应力值。进一步增加覆盖率无法消除表面的残余压应力高值区域,但是通过提高冲击处理的搭接率可以有效地降低材料的表面拉应力,从而显著提高处理后S30408材料的表面质量。
Based on the Johnson-Cook equation, a three-dimensional finite element model of ultrasonic impact treatment was established to study the dynamic process of austenitic stainless steel S30408 treated by ultra- sonic impact. The influences of coverage rate, overlap rate and impact times on the residual stress distribution, plastic deformation and morphology of the surface layer were analyzed. The results showed that the increase of the coverage raised the compressive stress on the surface of the material after shock treatment, and reduced the maxi- mum tensile stress at the edge of the impact pit. The high value region of tensile residual stress couldn＇t be eliminated by continuous increase the coverage. However, the surface tension stress of the material could be effectively reduced by increasing the lapping rate of the impact treatment, and the surface quality of the S30408 after treatment was remarkably improved.
出处
《化工装备技术》
CAS
2017年第4期20-27,共8页
Chemical Equipment Technology
关键词
超声冲击
有限元
残余应力
不锈钢
覆盖率
搭接率
Ultrasonic impact
Finite element
Residual stress
Stainless steel
Coverage rate
Overlap rate
