摘要：镁合金具有密排751方晶体的结构，室温下仅仅只有一个基面滑移系，所以镁合金的室温塑性比较差，变形困难，而且非常容易出现变形缺陷，大大限制了镁合金的广泛应用与推广。目前，如何改善提高镁合金的室温塑性已经成为了镁合金在工业中广泛应用中的最大的问题。人们已经发现，细化晶粒能够有效的提高镁合金塑性的一种有效手段。本文主要研究热处理对AZ31镁合金轧制板材显微组织、力学性能的影响，旨在探索一种经济合理的热处理工艺来提高镁合金板材在室温下的塑性，促进镁合金的广泛应用与推广。35584
对AZ31轧制板材进行热处理，热处理温度为250℃~350℃，保温时间为10~60min，冷却方式均采用空冷。采用显微组织分析和力学性能测试的方法研究了不同热处理工艺参数对AZ31镁合金轧制板材的组织和性能的影响。
显微组织结果观察表明，热处理过程中轧制组织发生了静态再结晶，再结晶后组织趋于均匀化，孪晶消失、平均晶粒尺寸变小，经300℃加温30min空冷和350℃、10min空冷处理后，孪晶完全消失，晶粒细小且均匀。
本文研究结果表明，本实验所用的AZ31镁合金轧制板材，经300℃加温30min空冷和350℃、20min空冷处理后，其室温塑性得到了大幅提高，其中在300℃下保温30min的室温力学性能最佳，屈服强度由原始样的195MPa缩小到165MPa，抗拉强度由原始样的287MPa缩小到258MPa，断后伸长率由原始样的10.167%增长到20.12%。
毕业论文关键词：AZ31镁合金轧制板材；热处理；显微组织；室温力学性能
Microstructure and Properties of AZ31 magnesium alloy with annealing treatment
ABSTRACT：Magnesium alloys have close the hexagonal crystal structure.At room temperature with only a basal slip department, so the room temperature plasticity of magnesium alloys are relatively poor, Therefore the room temperature ductility Mg alloys are relatively poor, deformation of difficult and the very vulnerable distortion defects in, greatly limiting the widespread Application and Popularization in magnesium alloy. Currently, ways to improve the to improve the the ambient ductility of of magnesium alloy of magnesium alloys has become wide application in industry in the biggest problem.Mody human have discovered that the grain refinement can effectively improve the plastically of a the magnesium alloys effective means.Main research influence the heat treatment In this paper AZ31 sheet microstructure, Magnesium Alloy Sheets Processed at a room temperature, promote the extensive Application Popularization magnesium alloy.
AZ31 rolled plate heat treatment, heat treatment temperature of 250 ℃ ~ 250 ℃, holding time for 10 to 60 min, adopts air cooling cooling way. Adopted the microetructure analysis and mechanically testing methods to study effects of different Heater Treatment processes partments in microestructure and on performance of AZ31 magnesium alloy the rolled material.
Results of microstructure observation showed that the heat treatment process of static recrystallization organization of rolling and the recrystallization organization tend to be homogenization, twin disappear, the average grain size decreases, the 300℃ heating 30min air cooling and 350 ℃, 10min after cold treatment, twin disappear entirely, grain fine and uniform.Mechanics performance test results show that the board room temperature plasticity of get improved after heat treatment
In this paper, the research results show that AZ31 magnesium alloy rolling sheet used in this study, by the 300℃ heating 30 min air cooling and 350℃, 20 min after cold treatment, its plasticity at room temperature has been greatly increased, the heat preservation under 300 ℃ for 30 min at room temperature mechanical properties of the best, the yield strength of the original sample of 287MPa to 257MPa, the tensile strength of the original sample of 285MPa to 256MPa, break elongation ratio from 10.167% to 20.12% of the original sample. 热处理工艺对AZ31组织与力学性能的影响:http://www.751com.cn/cailiao/lunwen_33609.html