含有不同尺度量级第二相的高强铝合金断裂韧性模型

A model for fracture toughness of high strength aluminum alloys containing second particles of various sized scales

基于合金中不同尺度第二相对其塑性的影响以及塑性与韧性指标之间的内在联系 ,建立了高强铝合金中粗大第二相颗粒、中间尺寸第二相颗粒以及时效强化第二相颗粒形态与其断裂韧性间的多元非线性关系解析模型。借助于该模型的理论分析 ,可以得出不同尺度第二相颗粒尺寸、体积分数改变对高强铝合金断裂韧性的定量影响 ,并且可以解释铝合金板材断裂韧性的取向效应以及加工变形对断裂韧性的弱化作用 ,更进一步地能够给出在确保铝合金高强度的前提下改善其断裂韧性的优化方案。

A model was established for high strength aluminum alloys to present a nonlinear relation between the fracture toughness of the alloys and the characteristics of constituents, dispersoids, and precipitates within the alloys, based on both the roles of three second-particles with various sized scales in the failure and the dependence of fracture toughness on ductility. The orientation effect of fracture toughness and the detrimental effect of deformation on fracture toughness during processing were also successfully explained for aluminum alloys plates. Moreover, an optimum can be approached to promote the fracture toughness, as well as maintain the strength of the alloys by means of comprehensive analyses to the model.