延性断裂韧度统计分布的数值模拟方法

Numerical Model Method for Statistic Distribution of Ductile Fracture Toughness

基于单试样延性断裂韧度的试验确定方法 ,本文建立了一种延性断裂韧度统计分布的数值模拟模型 ,可较好地处理各种非固定因素引起的延性断裂韧度的统计变异性。在计算机上易实现大样本量的模拟 ,得到较准确的延性断裂韧度的统计分布及其参数 ,同时还可进行敏感性分析。奥氏体不锈钢S316L焊缝金属的数值模拟计算结果表明 ,该方法是一种简单、有效和实用的数值模拟方法。敏感性分析表明 ,样本量对焊缝金属延性断裂韧度的统计分布及其参数具有较大的影响 ,由直接试验的小样本数据拟合得到的统计分布函数 ,会有较大的误差。

Based on the experiment measuring principle of ductile fracture toughness,a numerical model method was promoted for statistic distribution of ductile fracture toughness in this paper.Because this method can deal with the effect of random factors on ductile fracture toughness very well and produce the large number sample of J Ic easily,the more accurate statistic distribution and parameters of ductile fracture toughness cna be obtained by the manner.Meanwhile the method also analyzes the sensitivity of sample number.The calculation resultes of S316L weld metal shows that the numerical model method is sample,effective and applicable.The sensitivity analyses demonstrate that the number of samlpe affects greatly the accuracy of statistic distribution and parameters of ductile fracture toughness in weld metal.When the sample number of the J Ic is less,the more error well appear.