作　　者： ; ; ; ;

机构地区： 燕山大学机械工程学院

出　　处： 《塑性工程学报》 2006年第5期19-21,共3页

摘　　要： 通过连铸AZ31镁合金的单向拉伸实验，研究了该合金的超塑性变形性能及不同拉伸变形条件下的流变应力。结果表明，在温度为300℃～450℃，应变速率ε为4．25×10^-4s^-1的情况下，连铸ZA31镁合金表现出超塑性。在温度为400℃，应变速率ε为4．25×10-4s^-1时，延伸率增加了200％，具有较好的超塑性性能。用光学显微镜观察变形前后拉伸试样的微观组织发现：试样的初始晶粒尺寸约为15μm，在变形之后颈缩区域的晶粒长大现象不是很明显，晶粒沿着变形方向有所伸长，但晶粒形状基本保持为等轴状。 The tensile behaviors and flow stress of casting AZ31 Magnesium alloy at different deformation temperatures were investigated. According to the result, the alloy exhibited superplastic deformation behavior with the stain rate ε=4.25×10^-4 in a range of the deformation temperature from 300℃ to 450℃. It was found that the elongation percentage of the alloy at 400℃ with = 4.25 × 10^-4 s-1 is almost 200 %. The microstructures undeformed and deformed specimens were observed by optical microscope （OM）. The initial grain size of tensile specimens is about 15μm. The grain size growth near the necking zone is not obvious. Along the direction of deformation, it is found that grains become a little elongate, but the grain shape almostly maintains equiaxed.

关 键 词： 镁合金 单向拉伸 超塑性 流变应力

领　　域： [金属学及工艺]