摘要 本文就不同温度下轧制完成的镁合金板材进行固溶处理，随后利用拉伸试验机、光学显微镜、扫描电子显微镜以及X射线衍射仪，测定了AZ61镁合金板材的力学性能、观察金相显微组织和拉伸断口形貌、分析XRD衍射峰线的宽化效应，从而研究固溶处理对镁合金组织和性能的影响。研究结果表明，镁合金的抗拉强度随着固溶处理时的保温温度的升高，在380℃时达到顶峰，呈现先升高后降低的趋势。抗拉强度随着加热时间的延长，在0.5小时时综合力学性能最好，呈先上升后下降的趋势。拉伸断口形貌呈现韧窝状特征。固溶处理会引发发再结晶现象，使晶粒细化，从而使镁合金的强度下降、韧性增加。此次研究获得,AZ61最佳的热处理工艺是固溶温度是380℃保温0.5小时。52641

毕业论文关键词： AZ61镁合金；固溶处理；显微组织；力学性能 

 Effect of Solution Treatment on Microstructure and Properties of AZ61 Magnesium Alloy Rolled Sheet

Abstract This paper studies the effect of annealing treatment on the microstructure and properties of AZ61 magnesium alloy. After solution treatment of different kinds of rolled magnesium alloy sheet, then by using tensile testing machine ,optical microscopy, scanning electron microscopy and X-ray diffraction, observing and analysising the microstructure, mechanical properties, diffraction peak width and texture of  AZ61 magnesium alloy sheet .With the temperature increasing  increasing,the tensile strength of the magnesium alloy showed a trend of first increased and then decreased,and the strength was best at 380℃. With heating time extending ,the tensile strength of the magnesium alloy showed a trend of first increased and then decreased,and comprehensive mechanical performance best at 0.5 hour.While the solid solution can weaken the texture and strengthen the performance of magnesium alloy. The fracture morphology of the solid solution also showed a tough nest。The phenomenon of recrystallization can be occurred after solid solution treatment, which makes the grain refinement, so as to increase the toughness of the magnesium alloy.The results of studies shows that the best solution treatment technology was 380℃ for solid solution heat preservation 0.5h for AZ61 magnesium alloy.

Key word: AZ61 Magnesium alloy; solution treatment;mechanical properties;microstructure;

目  录

第一章  引言 5

1.1  选题的背景和意义 5

1.1.1  选题的背景 5

1.1.2  选题的意义 6

1.2  镁合金的塑性变形理论及成形工艺 7

1.2.1  镁合金的滑移 7

1.2.2  镁合金的孪生 7

1.2.3  影响镁合金孪生的主要因素 8

1.2.4  镁合金的塑性成形工艺 9

1.3  镁合金的热处理工艺 10

1.3.1  镁合金的退火处理 10

1.3.2  镁合金的固溶处理 11

1.3.3  固溶处理+人工时效 11

1.3.4  镁合金的人工时效 11

1.4  镁合金的研究现状及存在的问题 12

第二章  实验材料、研究方法及设备 12

2.1 实验材料 12

2.2 固溶处理工艺实验