摘要本课题利用电子束焊接2mm厚,体积分数为20%SiC颗粒增强铝基复合材料。通过金相检测、拉伸、硬度测试等方法,对焊缝组织和性能进行了分析。结果表明,界面反应产物,即针状Al4C3析出物的数量和大小随着热输入的减少而减少。当热输入降至78J/cm时,可以减少针状Al4C3的生成,熔合区中的SiC分布更加均匀。随着热输入的增加,断裂机制发生改变,由韧性向脆性转变,断裂面上的破碎颗粒数量减少,焊缝强度也延展性降低。同时,通过填充非增强焊缝夹层(铝硅钎料),可以发现熔池的过热程度得到有效控制,Al4C3脆性相减少。68176
毕业论文关键词 铝基复合材料;电子束焊;界面反应
毕业设计说明书(论文)外文摘要
Title Steel substrate surface plasma arc cladding microstructure and properties
Abstract
This topic using electron beam welded 2mm thick,, the volume fraction of 20% SiC particle reinforced aluminum matrix composites.By metallurgical testing, tensile, hardness testing and other methods, the weld microstructure and properties were analyzed.
The results show that the interface reaction product, Al4C3 needle size and number of precipitates with a reduction in heat input decreases. When the heat input drops 78J/cm, it can reduce the formation of Al4C3 needles, the fusion zone more uniform distribution of the SiC. As the heat input increases, the fracture mechanism is changed, changes from ductile to brittle fracture surface of the broken particles to reduce the number, the weld strength ductility. Meanwhile, non-reinforced welds by filling sandwich (Al-Si brazing), can be found in the bath overheating degree has been effectively controlled, Al4C3 brittle phase decreased.
Keywords aluminum matrix composites;Electron beam welding;Interface Reaction
目次
1概述 1
1.1 铝基复合材料概述 1
1.2 铝基复合材料焊接特点及主要连接方法 2
1.3 电子束焊接简介 5
1.4 铝基复合材料的常用制备方法 7
1.5 本课题研究的内容 7
2 试验材料及方法 8
2.1 试验材料与设备 8
2.2试验方法与研究方案 9
2.3 性能检测 11
3 焊接热输入对SiCp/Al直接电子束焊接头性能的影响 13
3.1对比实验设置 13
3.2接头宏观形貌分析 13
3.3 接头微观组织分析 14
3.4 接头力学性能分析 17
3.5 本章小结 18
4 焊缝中添加中间层对接头性能的影响 19
4.1对比实验设置 19
4.2接头宏观形貌分析 19
4.3 接头微观组织分析 20
4.4 接头力学性能分析 21
4.5 本章小结 21
5.焊接试件中存在的缺陷及防止措施 22
结 论