摘要:管状材料高压切变方法在制备薄壁复合管材方面具有极大的潜力。本文在前期研究基础上,以不同纯度的金属铝(99.98%和99.999%)为研究对象,在不同应变量下制备铝/铝复合管,并对其复合界面处组织特征和力学性能进行表征,对其组织演变和冶金结合效果进行分析。实验结果表明,大变形使晶粒破碎细化,随应变量增加,5NAl部分晶粒逐渐细化,经8圈变形后周向拉长,而4NAl部分晶粒较细小且晶粒尺寸达到1-2μm后其晶粒尺寸难以继续减小;在变形过程中5NAl和4NAl都出现了孪晶,且在8圈变形后4NAl部分孪晶数目增多;随应变量的增加,复合界面处硬度明显增加且在径向逐渐均匀;试样的剪切强度随应变量的增加而增加。
关键词 纯铝复合界面力学性能 显微组织 孪晶 剪切强度
Title Influence of strain on microstructure and mechanical properties of tube high-pressure shear
Abstract:Tube high-pressure shear in the preparation of thin-walled composite pipe has great potential. In this paper, based on the previous research, different purity aluminum (99.98% and 99.999%) under different strain are compound to prepare aluminum/aluminum composite tube. And the composite interface microstructure and mechanical properties are characterized. The
organization evolution law and metallurgical bonding effect is analyzed. By the experiment,the
grain size of the samples is refining. The grain size of part 5NAl diminish with the increase of strain, and stretch in circumferential direction under 8 turns. But the grain size of part 4NAl is smaller, and the size no longer to decrease until 1-2μm. The twins arise in part 4NAl and 5NAl, and the amount increase under 8 turns. The hardness between interface increase significantly and tend to uniform in radial direction and the shear strength increases with the increase of the strain.
Keywords pure aluminum;composite interface ;mechanical properties ;microstructure ;twins;shear strength
目 次
1 引言1
1.1研究背景..1
1.1.1累积叠轧技术(AccumulativeRoll-bonding)1
1.1.2等径角挤压变形法(EqualChannelAngularPressing).21.1.3高压扭转法(HighPressureTorsion)2
1.1.4管高压扭转法(HighpressureTubeTwisting)..2
1.1.5管高压剪切变形(TubeHighPressureShear)..2
1.2研究内容3
2 实验方法..5
2.1实验材料..5
2.2实验方案..6
2.3试样制备..6
2.4显微组织表征.6
2.5力学性能分析.7
2.5.1复合界面显微硬度测试7
2.5.2复合界面剪切强度测量7
3实验结果及分析8
3.1复合界面显微组织表征..8
3.2复合界面显微硬度测试.15
3.3复合界面剪切强度测试.16
结论17
致谢18
参考文献.19
1 引言
1.1 研究背景
如今现代工业对材料的要求越来越高。复合材料是由不同性能的材料结合而成,其具有较高的强度,和导电导热等性能,同时能够起到节约稀贵金属的作用,因而其在电子电力、航空航天、舰船、核工业等领域得到越来越多的应用,现具有极其广阔的应用前景。在复合材料中,复合管是将两种管材,通过变形结合,形成两种管材紧密结合的管状复合材料。其受外力作用时,管材各部分同时变形且界面粘合不分离[1],同时两种材料在性能上能够相互协调,提高其综合性能提高,使其具有更广的应用。如铜/铝复合管与原金属管相比,其不仅具有铝的耐腐蚀性,还具备铜的强度,同时还可以降低生产成本[2],具有很好的应用价值。 应变量对高压切变复合管组织与力学性能的影响:http://www.chuibin.com/cailiao/lunwen_205373.html