纳米压痕双斜率法的修正

分析了双斜率法的误差来源,即采用纳米压痕载荷与位移曲线求解材料的弹性模量和硬度,引入2种不同的修正因子并给出修正的双斜率法表达式,利用二维等效圆锥模型和三维真实Berkovich模型模拟幂强化型材料的纳米压入过程并求解修正因子,利用修正的双斜率法计算标准材料熔融硅的硬度和修正因子.结果表明,所得结果与其有限元模拟结果相近,从而验证了修正的双斜率法的有效性,同时,推测其对压头尖端钝化并不敏感.

Modified Two slope Method of Nanoindentation

Two slope method, which is used to calculate the materials' elastic modulus and hardness by using of nanoindentation force displacement curves, was modified by the introduction of two correction parameters that account for the effect of the two factors that influence the accuracy of this method most severely. The values of the correction parameters indentation on fused silica with Berkovich indenter were obtained by FEM simulation and comparison between the experiments and standard values of fused silica. Good agreements between the values from the two ways demonstrate the capability of the modified two slope method, and the insensitivity of the two slope method to the wear of the indenter tip.