A novel approach is proposed for evaluating equi-biaxial residual stresses (RS) from residual imprint displacement fields after spherical indentation. A unique region, where displacements are free from frictional effect, is first identified based on finite element analysis. Regression functions are proposed to relate imprint data with RS for a broad range of material properties. Digital image correlation (DIC) is employed for measuring the radial displacement fields. Experimental comparison of RS values from the present method and strain gauge showed the (maximum, mean) errors of only (10, 5) %. As the determined RS are accurate and reliable, the methodology can find more industrial applications compared with prior techniques.

提出了一种新方法，用于评估球形压痕后残余压痕位移场的等双轴残余应力 (RS)。首先基于有限元分析确定位移不受摩擦影响的独特区域。提出了回归函数将压印数据与 RS 相关联，以获得广泛的材料特性。数字图像相关（DIC）用于测量径向位移场。来自本方法和应变仪的 RS 值的实验比较表明（最大、平均）误差仅为 (10, 5) %。由于确定的 RS 准确可靠，与现有技术相比，该方法可以找到更多的工业应用。