摘要镁属于密排六方结构金属,塑性变形能力差,很难加工成板、带、棒、型材,因而其应用受到很大限制。本课题研究一种超细晶金属材料制备方法,涉及成型技术领域,具体是一种AZ31镁合金多面循环轧制方法:采用线切割切取方块界面的镁合金板材,不同温度轧制后,将试样绕轧制轴方向顺时针旋转90°,继续轧制构成轧制循环。通过循环轧制,可以得到比较均匀的等轴组织,晶粒尺寸得到细化,晶粒平均尺寸为7µm;同时织构强度明显弱化,纳米孪晶出现,力学性能可达到延伸率13%,拉伸屈服强度330MPa,抗拉屈服强度360MPa。实现了AZ31合金的组织细化和力学性能的改善。61000
毕业论文关键词:镁合金 多面循环轧制 组织细化
毕业设计说明书(论文)外文摘要
Title Magnesium alloy multi-faceted cycle rolling method
Abstract The magnesium alloy has the close-packed hexagonal structure.So it is bad in the plastic deformation and very difficult to process the sheet,the belt,the bars,the sectional bars,thus there is much limit in its application.The research an ultrafine grained metallic materials preparation, relates to the field of forming technology, specifically a AZ31 magnesium alloy multi-faceted cycle rolling method. By wire cutting cut the box interface magnesium alloy sheet the different temperature rolling after the sample around the rolling axis direction clockwise rotation of 90 °, to continue rolling constitute rolling cycle. Cycle rolling uniform equiaxed grain size can be refined, the average grain size of 7 μm; the texture strength significantly weakened, nano twins, the mechanical properties of up to 13% elongation, yield strength of 330MPa, tensile strength 360MPa. AZ31 alloy microstructure refinement and improvement of the mechanical properties.
Keywords: magnesium alloy sheet;multi-directionally forged; ultrafine grain
1 绪论 1
1.1 前言 1
1.2 变形镁合金的分类及牌号 2
1.3 镁合金的应用 3
1.4 镁合金的变形机理 4
1.5 镁合金的轧制方式 6
1.6 本课题研究创新点 8
2 材料与研究方案 9
2.1 研究材料 9
2.2 仪器设备 9
2.3 方案设计及步骤 9
3 研究结果及分析 12
3.1 显微组织观察分析 12
3.2 力学性能结果分析 13
3.3 动态再结晶分析 14
3.4 孪晶组织分析 15
3.5 织构观察分析 16
结 论 18
致 谢 19
参考文献 20
1 绪论
1.1 前言
随着航空和汽车工业的迅速发展,对通过降低产品的自重以降低能源消耗和减少污染提出了更迫切的要求,电子产业尤其是通讯业的飞速发展对电子器材的薄壁轻量化提出了更高的要求,这给镁合金的进一步发展带来了巨大契机。