摘要为了改善镁合金的力学性能,目前的工作主要集中在研究织构、微观组织晶粒尺寸对力学性能的作用规律方面。然而,由于镁合金织构和晶粒尺寸密切相关,加上织构演变的复杂性。通过弯曲轧制和平轧组合的加工方式以及异步轧制等不同轧制工艺成功制备了织构类型和强弱不同的细晶镁合金样品,接着选取两组异步轧制样品进行退火处理,得到了晶粒尺寸宽分布的两个系列试样,而每个系列试样的织构在退火前后基本保持不变,从而最终将晶粒尺寸和织构这两大影响镁合金力学性能的因素分离开来。利用金相观察、力学性能表征、极图和取向分布函数测试等手段分析了不同轧制工艺下的组织、性能的演变,重点探讨了织构种类及其数量对镁合金的影响。结果表明,具有不同织构种类和数量的镁合金其拉伸屈服强度和晶粒尺寸间均符合一定关系。62176

毕业论文关键词： 镁合金；织构；弯曲轧制； 异步轧制 ；力学性能

Effect of texture on mechanical properties of magnesium alloy

Abstract

In order to improve the mechanical properties of magnesium alloys, the current work is mainly focused on the study of texture, grain size effect of microstructure on the mechanical properties of the aspects of the law. However, since the magnesium alloy texture and grain size are closely related, with the evolution of textures complexity. By bending a rolling mill combination peaceful way of processing and asynchronous rolling different rolling process successfully prepared texture and strength of the different types of fine-grained magnesium alloy samples, and then select two asynchronous rolled annealed samples obtained wide grain size distribution of the two series of samples, each sample texture series before and after the annealing remained unchanged, thus eventually grain size and texture of these two factors affect the mechanical properties of magnesium alloys separated Come. Observed by optical, mechanical characterization, pole figures and orientation distribution function testing and other means to analyze the evolution of different rolling process under the organization's performance, focusing on the effects of texture types and quantity of magnesium alloy. The results showed that different texture types and quantities of magnesium alloy between its tensile yield strength and grain size are in line with a certain relationship.

Keywords: magnesium alloy;texture;alternating bending rolling; asymmetric s rolling; mechanical properties

目录

第1章 绪论 1

 1.1 前言 1

 1.2 镁合金的塑性变形模式 1

  1.2.1 镁合金的滑移 1

  1.2.2 镁合金的孪生 2

 1.3 镁合金的织构类型 4

 1.4织构对镁合金力学性能的影响 6

 1.5影响镁合金织构的因素 7

 1.6镁合金织构控制 8

  1.6.1 镁合金塑性成型类型对织构的影响 8

  1.6.2 稀土元素合金化与镁合金织构随机化 9

 1.7 织构的表示方法 9

 1.8课题研究内容 12

第2章 实验材料及方案 13

 2.1实验材料 13

 2.2 实验方案 14

  2.2.1 弯曲轧制实验