摘要为了获得优质TA2与304不锈钢的焊接接头，本课题使用激光焊接来焊接TA2与304不锈钢。即研究在激光焊接技术条件下钛和钢的焊接性。焊接性包括两个方面。一是接合性能，二是使用性能。本课题就是从这两个方面对钛和钢的激光焊工艺进行研究的。86148

通过比对不添加和添加过渡层，本课题首先对钛和钢的接合性能进行研究。发现TA2/304SS直接对接焊焊后就发生开裂，并断裂在钢侧。这是由于焊缝内生成了大量的脆性Ti-Fe系列化合物。因此必须消除或减少焊缝中的金属化合物的生成，从而改善接头的质量。

本课题首先采用单独的V作为过渡金属来连接TA2与304不锈钢，分别采用2mm、3mm、4mm、5mm宽的V过渡段时，可以有效的阻止Ti与Fe的结合，接头是由TA2/V接头，未熔V和V/304接头三个部分组成。当过渡段厚度为5mm时，接头强度最高，为314。2MPa。加入1mmV过渡层时，焊后试样断裂，界面已生成脆性化合物。

本课题还采用了Cu/V复合过渡段。当分别加入2mm-5mm宽的Cu/V过渡段时，接头由TA2/V接头、未熔V区、V/Cu接头、未熔Cu区、Cu/304接头五个部分组成。当加入5mm宽的复合过渡段时接头强度最高，为297。3MPa。采用1mmCu/V过渡层时，在两条焊缝中间出现未熔钒层，断裂起源于此，接头强度为135。8MPa。当添加1mmCu，0。5mmV进行焊接时，未熔钒层厚度减少，拉伸强度为243。3MPa。

毕业论文关键词：TA2；304不锈钢；激光焊接；过渡段

Abstract In order to obtain the high quality TA2 and 304 stainless steel welded joints, this paper uses the laser welding technology to weld TA2 and 304 stainless steel。 In another word, we study the welding property of TA2 and 304 stainless steel under the laser welding。 The welding property includes two aspects。 One is the bonding performance, another is the using performance。 In this paper, we studied from those two aspects。

By comparing whether adding the transition layer or not, in this paper, we study on the bonding properties of TA2 and 304 stainless steel first。 It is found that the cracking occurs after TA2/304SS direct butt welding。 This is due to the formation of a large number of brittle Ti-Fe series compounds in the weld。 So we can improve the quality of the joint by replacing the metal compound with the solid solution in the weld。

In this paper, first, we used the separated V as a transition metal to connect TA2 and 304 stainless steel, respectively using 2mm, 3mm, 4mm, 5mm wide V transition segment。  It can be effectively prevent the combination of Ti and Fe, the joint is made of TA2/V joints, not fused V and V/304 three parts, each interface is only solid solution。 The thickness of highest strength of the joints is 5mm, there are 314。2MPa。 When the 1mmV transition layer is added, the joint is broken, and the brittle compound is formed in the middle。 

This paper also uses the Cu/V compound transition section。 When the 2mm-5mm wide Cu/V transition section is added, the joint is composed of TA2/V joint, V zone, V/Cu joint, Cu joint, Cu/304 joint。 The highest strength of the joint is the transition section of the 5mm, which is 297。3MPa。 When the 1mmCu/V transition layer is used, there is no V layer in the middle of the two welding seam。 The fracture originated from this, the joint strength is 135。8MPa。 On the base of 1mmCu/V transition layer, we reduced the V layer’s width to 0。5mm。 Two weld junction without melting V layer’s thickness has reduced,  which improve the tensile strength to 243。3MPa。 

Key Words:TA2;304 stainless steel; laser welding; transition section

目 录

第一章 绪论 1

1。1 引言 1

1。2 钛与钢的焊接性分析