Microstructure-based analysis of fatigue behaviour of Al-Si-Mg alloy  

基于微结构变化的Al-Si-Mg合金的疲劳行为分析(英文)

作　　者：蒋小松[1] 何国求[1] 刘兵[1] 范宋杰[1] 朱旻昊[2] 

机构地区：[1]同济大学材料科学与工程学院上海市金属功能材料开发应用重点实验室,上海200092 [2]西南交通大学牵引动力国家重点实验室,成都610031

出　　处：《Transactions of Nonferrous Metals Society of China》2011年第3期443-448,共6页中国有色金属学报（英文版）

基　　金：Project (2007CB714704) supported by the National Basic Research Program of China;Project (50771073) supported by the National Natural Science Foundation of China

摘　　要：The effects of microstructural characteristics on the fatigue behavior in Al-Si-Mg alloy were investigated. The dislocation substructures of Al-Si-Mg alloy were observed by transmission electron microscopy （TEM）. Dislocation evolution process of α（Al） matrix with [011] orientation of Al-Si-Mg alloy specimens was observed during fatigue process under different stress amplitudes and cycles. The results indicate that dislocation structure is closely dependent on stress amplitudes, and the density of dislocation in failure specimens increases with increasing stress amplitudes. The results show that Mg2Si and secondary silicon phase could have a strong hindrance effect on the movement of dislocations during the fatigue process. The fatigue behavior is strongly dependent on the microstructure of material.研究Al-Si-Mg合金的微结构对其疲劳性能的影响。利用透射电子显微镜观察不同条件下Al-Si-Mg合金中位错的结构,对同一应力幅下不同循环周次试样的基体(011)面进行位错观察。结果表明,Al-Si-Mg合金的位错结构随应力幅的变化而变化,并具有一定的规律性;Mg2Si与二次硅相对位错运动具有强烈阻碍作用。材料的疲劳行为强烈地依赖于的材料的微观结构变化。

关 键 词：Al-Si-Mg alloy DISLOCATION MG2SI secondary silicon phase 

分 类 号：TG115.57[金属学及工艺—物理冶金]