摘要
研究了 Al-Mg-Si 系合金6063在不同时效状态下的显微组织及循环形变特性,并结合其疲劳性能和断裂特征进行了讨论。结果表明,时效条件对显微组织和形变机制有明显的影响。在UA 和 PA 状态下,组织中的时效析出物为 GP 区,形变以位错切过的方式进行,形成不均匀的平面滑移带。在 OA 状态,组织中的时效析出物为β′相,位错绕过β′相,形成均匀的位错缠结。形变特性对合金的疲劳断裂形式有明显的影响。
The microstructure and deformation mechanisms in cyclic stress were studiedfor an Al-Mg-Si alloy 6063 treated with different aging conditions.A discussion in con-nection with fatigue properties and fracture mode of the alloy was performed.The resultsshow that the aging condition has considerable influence on the microstructure anddeformation mechanisms.In the UA and PA conditions which had GP zones,thedeformation was carried out in the cut off mode,the heterogeneous planar slip bands wereformed.In the OA condition which had precipitates,the dislocations were bowed out andthe homogeneous dislocation tangles were formed.The deformation behavior has consider-able effect on the fatigue fracture mode.
