摘要
针对一种高强钢,采用307Mo焊丝在Ar+N二元混合气体保护下进行机器人自动化PMIG焊接实验,主要研究活性氧元素的对焊接接头组织与性能的影响。并对焊接接头的组织、相组成、显微硬度及拉伸性能进行了分析。结果显示:氧元素的加入使得焊接接头固溶氮含量提升,焊缝组织均匀,晶粒细化,δ铁素体数量减少。XRD物相分析发现焊缝金属主要由奥氏体组织组成,此外还形成氮的化合物。力学性能显示氧元素的加入提高了焊缝金属的硬度以及拉伸性能,但是如何避免焊缝产生气孔等缺陷有待于进一步的研究与分析。
In this dissertation,the automatic PMIG welding experiment with 307 Mo welding wire is carried out on a high strength steel under the Ar＋N two element mixed gas.The effect of reactive oxygen element on the microstructure and properties of the welded joint is studied and its microstructure,phase composition,microhardness and tensile properties are analyzed.The results show that the addition of oxygen makes the content of the solid solution nitrogen of the welding joint increased and the microstructure of the welded joints uniform,the grain size refined and the number of the delta ferrite reduced.XRD phase analysis shows that the weld metal is mainly composed of austenite,and the compound of nitrogen is formed.The mechanical properties show that the addition of oxygen can improve the hardness and tensile properties of the weld metal,but how to avoid the defects such as weld porosity and so on,which needs to be further studied and analyzed.
出处
《机械制造与自动化》
2017年第4期163-165,181,共4页
Machine Building & Automation
基金
江苏省自然科学基金(BK20131261)
关键词
高强钢
氧气
氮含量
性能
high strength steel
oxygen
nitrogen content
property
