Al-7Si-0.45Mg铸造合金断裂韧性统计模型

STATISTICAL MODEL FOR FRACTURE TOUGHNESS OF A MODIFIED Al-7Si-0.45Mg CAST ALLOY

本文根据Al-7Si-0.45Mg铸造合金断裂微观特征的观察、对合金各种力学性能的测量和影响因素的分析以及对由此分析得出的该合金断裂组织控制参量——较大共晶Si粒子的线尺寸及其分布的观察和定量研究,提出了符合该合金断裂过程的微观断裂机理,并把该合金断裂的组织控制参量与断裂性能相联系,在铸造合金中建立了符合合金微观断裂机理的断裂统计模型。

The statistical model for the fracture toughness of a modified Al-7Si-0.45Mg cast alloy has been proposed on the basis of analysis of the correlationbetween the size distribution of crack nuclei and Si particles and of the microme-chanism of fracture. The suitable criterion of fracture toughness according to themodel has been given. The model has found a good explanation for the fracture.feature, fracture toughness and microstructure, and agreed with the experiments-very well.