纯镍N6填丝等离子焊接工艺及接头组织性能的研究

发布时间：2018-07-02 07:03

本文选题：工业纯镍N + 填丝等离子焊接　；参考：《稀有金属》2015年02期

【摘要】：试验采用等离子弧焊设备对工业纯镍N6板材进行填充焊丝等离子焊接工艺试验。借助光学显微镜(OM)、扫描电镜(SEM)、能谱分析(EDS)、X射线衍射仪(XRD)和显微硬度计等手段分析了焊接接头的微观组织和力学性能。结果表明:采用合理的焊接工艺参数可以得到成形良好的焊缝,填丝焊接接头抗拉强度为333 MPa,其抗拉强度达到母材强度的97.6%,不填丝焊接接头抗拉强度为240 MPa,达到母材强度的70.5%;母材为均匀细小的等轴晶,填丝接头焊缝处呈树枝状结晶且晶粒粗大,热影响区靠近熔池部分的晶粒过热长大,靠近母材部分为均匀细小的等轴晶;填丝接头基体为γ-Ni组织,同时存在γ'(Ni3(Al,Ti)C)强化相,填丝接头拉伸断口表现为韧-脆混合断裂,焊接接头硬度最低值出现在热影响区;与母材相比,不填丝接头焊缝区与热影响区晶粒粗大,其基体组织为单相奥氏体,不填丝接头拉伸断口表现为脆性断裂,硬度最低值出现在接头热影响区。
[Abstract]:Plasma arc welding equipment was used to test the filling wire plasma welding process of industrial pure nickel N 6 sheet. The microstructure and mechanical properties of welded joints were analyzed by means of optical microscope (OM), scanning electron microscope (SEM), energy dispersive analysis (EDS), X-ray diffraction (XRD) and microhardness meter. The results show that the well-formed weld can be obtained by using reasonable welding parameters. The tensile strength of the filler wire welded joint is 333 MPA, and its tensile strength is 97.6 of the base metal strength, and the tensile strength of the unfilled wire welded joint is 240 MPA, which reaches 70.5% of the base metal strength; the base metal is uniform and fine equiaxed crystal, The weld seam of the filler wire joint is dendritic with coarse grain size, the grain near the weld pool in the heat affected zone is overheated and grows, and near the base metal part is uniform and fine equiaxed crystal, and the matrix of the filler wire joint is 纬 -Ni structure, and there is 纬'(Ni3 (AltaiTi) C) strengthening phase in the filler wire joint. The tensile fracture of the filler wire joint is ductile-brittle mixed fracture, the lowest hardness of the welded joint appears in the heat-affected zone, compared with the base metal, the grain in the weld zone and the heat-affected zone of the non-filler wire joint is coarse, and the matrix structure is single-phase austenite. The tensile fracture of the unfilled joint is brittle fracture and the lowest hardness occurs in the heat-affected zone of the joint.
【作者单位】：兰州理工大学材料科学与工程学院;
【基金】：甘肃省科技支撑计划项目(1104GKCA051)资助
【分类号】：TG456.2;TG407

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