2205双相不锈钢焊接接头微观组织调控技术研究

摘要 2205双相不锈钢拥有铁素体和奥氏体组织，故而双相不锈钢具备了两相组织的特点。通过合理控制化学成分与应用热处理工艺，使得双相不锈钢兼顾奥氏体不锈钢以及铁素体不锈钢的优点。其中，双相不锈钢具有良好的韧性、强度、耐腐蚀性以及焊接性。本文采用手工电弧焊对2205双相不锈钢进行焊接实验。在同种焊接位置下，研究不同工艺参数对焊接接头微观组织、力学性能以及腐蚀性能的影响。结果显示，随着焊接热输入的增加，焊缝区奥氏体相明显增多，而热影响区奥氏体含量远远低于焊缝。并且，由于冷却速度过慢，大大增加了有害二次相析出的几率。通过对焊接接头进行拉伸以及弯曲试验，分析得出随着焊接热输入的增加，其抗拉强度达到802.9MPa、伸长率达到9.57%，且在弯曲试样中未发现裂纹，由此得出焊接接头符合要求。在显微硬度测试中，得出热影响区的硬度最高，母材次之，焊缝最低，这与焊缝组织中奥氏体相的含量紧密相关。58960
毕业论文关键词：双相不锈钢；手工电弧焊；微观组织；力学性能
Abstract 2205 duplex stainless steel is composed of ferrite and austenite phase, so the duplex stainless steel has the characteristics of two-phase structure. By controlling the chemical composition and the application of heat treatment process, the advantages of duplex stainless steel, austenitic stainless steel and ferritic stainless steel are also considered. The duplex stainless steel has good toughness, strength, corrosion resistance and welding resistance. In this paper, 2205 duplex stainless steel is welded by manual arc welding. Effect of different process parameters on microstructure, mechanical properties and corrosion resistance of welded joint was studied under the same welding position. The results show that with the increase of welding heat input, the austenite phase in the weld zone increases obviously, while the austenite content in the heat affected zone is much lower than that of the weld. And, as a result of speed too slow, which greatly increases the risk of the harmful secondary phase precipitation. Through the tensile and bending test of welded joint analysis, obtained with the increase of heat input welding, the tensile strength reached 802.9MPa, elongation reached 9.57% and in bending specimens were not found to crack, so that welding joint meets the requirements. In the micro hardness test, it is concluded that the heat affected zone is the highest hardness, the second is the base metal, the minimum of the weld, which is closely related to the content of the austenite phase in the microstructure of the weld.
Key words: DSS; SMAW; microstructure; mechanical properties

第一章绪论..1

1.1双相不锈钢概述1

1.22205双相不锈钢1

1.2.12205双相不锈钢组织1

1.2.22205双相不锈钢的力学性能2

1.2.32205双相不锈钢的耐蚀性.3

1.3双相不锈钢焊接性的研究..3

1.3.1双相不锈钢双相比的控制.3

1.3.2双相不锈钢焊接制约因素.5

1.3.3双相不锈钢的焊接研究..6

1.4课题的研究目的、选题意义及主要研究内容7

1.4.1选题的意义及目的.7

1.4.2主要研究内容8

第二章试验材料及过程.9

2.1试验材料9

2.2焊接试验方法与过程.9

2.2.1焊接方法及设备..9

2.2.2焊接过程10

2.3焊接接头的试验分析..10

2.3.1金相组织及相比例分析10

2.3.2拉伸、弯曲试验11

2.3.3冲击试验及断口扫描电镜分析12

2.3.4显微硬度测试.13

2.3.5焊接接头腐蚀性能测试13

第三章接头性能测试与分析.15

3.1焊接接头微观组织与相比例分析15 2205双相不锈钢焊接接头微观组织调控技术研究:http://www.751com.cn/cailiao/lunwen_63984.html