材料性能和压入深度对球压痕堆积/沉陷的影响

Influence of Material Properties and Indentation Depth on Pile-up/Sink-in of Spherical Indentation

压痕硬度受材料堆积/沉陷影响明显,通过有限元仿真技术分析了材料性能和压入深度对堆积/沉陷的影响,结果表明,随着弹性模量与屈服强度比、压入深度增加或硬化指数减小,材料的沉陷量减小而堆积量增加;当弹性模量与屈服强度比相对较小时,堆积/沉陷受硬化指数的影响较明显。根据建立的等效应变与材料堆积/沉陷的拟合函数关系,可以判断压痕过程的堆积/沉陷状态,从而对计算得到的压痕硬度的准确性进行评判。

Taking into account of the significant impact of pile-up/sink-in on indentation hardness, the influence of material properties and indentation depth on pile-up/sink-in was analyzed using the finite element simulation technology. The results show that the amount of sink-in decreases or pileup increases with the increase of ratio of the elastic modulus and yield strength, indentation depth, or decrease of work hardening; the influence of work hardening on pile-up/sink-in is bigger when the ratio of the elastic modulus and yield strength is smaller. A fitting function relationship between the equivalent strain and pile-up/sink-in was established to determinate of the amount of pile-up/sink- in, so the accuracy of indentation hardness can be evaluated.