基于能量的球压痕硬度的计算方法

An Energy-based Method for Calculating Spherical Indentation Hardness

采用Oliver-Pharr方法计算压痕硬度容易受到卸载斜率计算偏差的影响。为了提高压痕硬度计算的准确度,减小卸载斜率对压痕硬度的影响,假定最大压入深度下的接触半径与完全卸载后的压痕半径相等,根据Hertz接触理论,基于压痕功与压痕深度的线性关系,建立了压痕硬度与压痕功的显式模型。压痕试验的结果表明,基于能量的压痕硬度计算方法能够有效提高压痕硬度计算的准确度,可以满足工程实际需要。

The accuracy of initial unloading slope has large influence on indentation hardness by using Oliver-Pharr method. In order to improve the accuracy of calculation of indentation hardness and reduce the influence of initial unloading slope on indentation hardness, the contact radius at the maximum depth was assumed to be equal to the residual indentation radius. Based on the Hertz contact theory and using the linear relationship between indentation energy and indentation depth, an explicit model was established between indentation hardness and indentation energy. The results of indentation experiment show that the accuracy of indentation hardness is effectively improved and can meet practical engineering requirements by using the energy-based method.