摘要本文研究经过不同热处理的AZ31B镁合金、LY12和7075铝合金进行ECAP变形,挤压道次对它们微观组织和力学性能的影响,并分析造成该种影响的原因。结果表明:
(1)镁合金晶粒尺寸随变形道次增加逐渐降低,之后晶粒尺寸趋于稳定;试样的宏观硬度值随变形道次增加,并趋于稳定;随变形道次增加,镁合金的屈服强度逐渐降低,抗拉强度先升高后降低,延伸率持续增加;
(2)LY12和7075铝合金在高温下ECAP 变形后,晶粒并未发生明显的细化,反而粗化。随着挤压道次的增加,LY12铝合金的宏观硬度先减小后增大,延伸率先增大后减小,抗拉强度先减小后增大,屈服强度持续增大;7075铝合金的宏观硬度不断减小,随后趋于平缓;延伸率持续增加;抗拉强度先减小后趋于平缓;屈服强度先减小后增大。
关键词 等通道转角挤压 AZ31镁合金 LY12铝合金 微观组织 力学性能6626
毕业设计说明书(论文)外文摘要
Title Properties of mechanical in ECAP on light alloys
Abstract
This paper studied the AZ31B magnesium alloy, the LY12 and 7075 aluminum alloy which processed different heat treatment make ECAP deformation. It found the ECAP pass how to play a role on microstructure and properties of mechanical in three alloys and analyzed the reason that. The results showed:
⑴The magnesium alloy grain size gradually reduced with deformation pass increased, stabilizing grain size later; The macro-hardness specimen with deformation times and kept stable; The yield strength of magnesium alloy gradually decreased; The tensile strength first increased and decreased then; The elongation continued to increase with deformation pass increased.
⑵ LY12 and 7075 aluminum alloys made ECAP deformation at elevated temperature. Their grain not only didn’t refined significantly, but also coarsening. With the pass increasing, LY12 aluminum alloy’s hardness decreased at first and increased later; The elongation first increased and decreased then; The tensile strength first decreased and increased then; The yield strength increased continuously. At the same situation ,7075 aluminum alloy’s hardness decreased continuously, and then became stable ; The elongation increased continuously; The tensile strength decreased firstly and then became stable; The yield strength first decreased and increased then.
Keywords Equal channel angular pressing AZ31 Mg alloy LY12 Al alloy 7075 Al alloy Microstructure Mechanical Properties
目 录
1 绪论 1
1.1 剧烈塑性变形 1
1.2 等径角挤压 2
1.3 镁与镁合金简介 7
1.4 铝和铝合金的简介 8
1.5 本文的研究内容和意义 10
2 实验方法和内容 12
2.1实验方案设计 12
2.2 试样制备 12
2.3 等通道角挤压(ECAP)实验 13
2.4 实验分析方法 14
3 ECAP对AZ31B镁合金的显微组织和力学性能的影响 16
3.1 ECAP挤压道次对显微组织观察 16
3.2 ECAP挤压道次对力学性能的影响 18
3.3 本章小结 21
4 ECAP对LY12铝合金的显微组织和力学性能的影响 23
4.1 ECAP挤压道次对LY12铝合金显微组织观察 23
4.2 ECAP挤压道次对LY12铝合金力学性能的影响 24
4.3 本章小结 28
5 ECAP对7075铝合金的显微组织和力学性能的影响 30 ECAP对轻合金的力学性能影响研究+文献综述:http://www.youerw.com/cailiao/lunwen_4244.html