ABSTRACT

Indentation scaling relationships intend to guide indentation experiments and help understand the indentation hardness. In the present study, dimensionless functions were obtained by fitting a series of numerical results of the cross-scale indentation tests based on a strain gradient plasticity theory. The closed-form indentation scaling relationships were found between dimensionless material properties and indentation responses, which were non-dimensionalised by a representative stress. The closed-form expressions were of high accuracy with both the numerical results and the experimental data. Forward and reverse analysis were then established and discussed, providing the indentation scaling relationships a quantitative result. The explicit definition of the representative stresses made it possible to obtain the specific relationship between indentation responses and each material parameter. Together with some pre-determined material parameters, the material intrinsic length was able to be derived from the indentation tests. The present work significantly enhanced the value of the cross-scale indentation scaling relationships, providing great convenience in guiding instrumented tests.

摘要

压痕比例关系旨在指导压痕实验并帮助理解压痕硬度。在本研究中，通过基于应变梯度可塑性理论拟合一系列跨尺度压痕试验的数值结果，获得了无量纲函数。在无量纲的材料特性和压痕响应之间发现了闭合形式的压痕缩放关系，而压痕响应没有通过典型应力进行尺寸标注。封闭形式的表达式在数值结果和实验数据上都具有很高的准确性。然后建立和讨论正向和反向分析，为压痕缩放关系提供定量结果。代表应力的明确定义使得获得压痕响应与每个材料参数之间的特定关系成为可能。连同一些预定的材料参数，材料固有长度能够从压痕测试中得出。本工作显着提高了跨尺度压痕尺度关系的价值，为指导仪器测试提供了极大的便利。