摘要
为了精确测量边缘产生凸起的超显微硬度压痕,采用高分辨率且能获得压痕三维形貌的激光扫描共聚焦显微镜,获得压痕边缘复杂的三维凸起结构。对压痕的三维形貌数据进行分析,利用压痕对角线方法提取压痕的4个角点,计算超显微硬度。然而,压痕对角线法并不能反映残余压痕的复杂结构,尤其是边缘凸起结构。在测量压痕三维形貌的基础上,为寻找更符合接触力学和压痕形成规律的压头与试样的接触面积,提出了基准平面的概念。通过对压痕面积函数进行微分,寻找最优的基准平面位置,既考虑压痕的边缘凸起,也能很好地反映接触面积。实验结果表明,通过接触力学规律寻找到的最优基准平面测量硬度,其测量误差小于±1.5%、稳定性小于1%。基准平面法可以稳定且准确地得到更符合硬度定义的硬度值。
To accurately measure the ultra-micro-hardness indentation by considering the pile-up,a highresolution laser scanning confocal microscope was used to obtain the 3D morphology of the residual indent in this study.The four corners of indentation were then extracted to calculate the ultra-micro-hardness value using the indentation diagonal method.However,this traditional method cannot accurately reflect the complex structure of the residual indenter,in particular,the pile-up.Taking advantage of the knowledge on the 3D shape of the indent,a datum plane concept is proposed to determine the true contact area in accordance with the contact mechanics.It was found that the contact area determined by the datum plane at the inflexion point of the area function differentiated by the depth is a good indication of the contact area,even considering pile-up.The experimental results show that the hardness values measured by the optimal datum plane obtained by the contact mechanics law are<±1.5%error and<1%stable.The reference plane method can obtain a more stable and accurate hardness value that is more consistent with the definition of hardness.
作者
石伟
张凯林
侯晓东
SHI Wei;ZHANG Kai-lin;HOU Xiao-dong(Changcheng Institute of Metrology and Measurement,Aviation Industry Corporation of China,Ltd.,Beijing 100095,China;School of Instrumentation and Optoelectronic Engineering,Beihang University,Beijing 100191,China;Department of Stress Analysis,Centre of Excellence for Advanced Materials,Dongguan 523808,China)
出处
《光学精密工程》
EI
CAS
CSCD
北大核心
2021年第5期1014-1023,共10页
Optics and Precision Engineering
基金
国家“十三五”技术基础项目(No.JSJL2016205A014)
广东省引进创新团队项目(No.2016ZT06G025)。
