硬度影响压痕弹塑性行为的有限元分析

以具有不同硬度40Cr为研究对象,根据集中载荷下的接触模型和赫兹理论,计算了压痕接触半径和压痕附近弹性区域的表面局部接触应力,并采用有限元法,分析硬度物理量对压痕弹塑性行为、局部接触应力、卸载后保留在内部的残余应力的影响,探讨压痕参数、压痕接触应力、残余应力与硬度之间的关系以及载荷增加时它们的发展.结果表明,相同载荷下塑性隆起量、压痕接触半径、压痕量和塑性区范围随着硬度值的提高而减小,弹性回弹量、最大接触应力和残余应力随硬度提高而增加;压痕周围处接触应力和残余应力、其分布范围和塑性区域随载荷的增加而增加.

Finite Element Analysis on the Elasto-Plastic Mechanics of the Indentation Affected by the Hardness

Based on the elastic hertz theory; the eontaet radius and the contact stress are calculated to describe the elastic mechanics by using the indentation model on the 40Cr with different hardness. The influence of the hardness on the indentation elasto-plastic mechanics, the contact stress under the load, residual stress after unloading around the indentation are analyzed by using the finite element method. Moreover, the relationship among the indentation parame- ters, contact stress, residual stress and the hardness, including development of them with the increasing load are dis- cussed. The result shows the plastic pile-up, the contact radius, the indentation depth and the size of plastic region are decreased with the increasing of the hardness. Elastic recovery, the maximum contact stress and residual stress are in- creased with the increasing of the hardness. And the contact stress, residual stress, the distribution of the contact stress and the residual stress around the indentation, and the size of plastic region are increased with the increasing of the load.