中文摘要：

通过扫描电镜、高温拉伸试验机和高温蠕变试验机等对GH3230高温合金钨极氩弧焊接接头的显微组织和高温性能进行了研究。结果表明：焊缝组织主要由平衡凝固γ＇-FeCrNiC镍基固溶体、少量的颗粒状γ-Ni3Al和MC碳化物组成，呈等轴树枝状；热影响区的组织与母材的相当，但晶粒更粗大；焊接接头具有良好的高温性能，其在927℃下的高温抗拉强度为244MPa，与母材的相当，在927℃和62MPa下的高温蠕变寿命为38.82h，高于母材的；高温拉伸和高温蠕变试验后的接头断口形貌与母材的基本一致，分别为韧窝型和沿晶断裂。

英文摘要：

The high temperature properties and microstructure of GH3230 alloy argon arc welded joint were investigated by SEM, high temperature tensile test and high temperature creep test. The results indicate that the equiaxial dendritic microstructure of welded seam was made up of equilibrium frozen Ni based solid solution, γ-FeCrNiC, a little bit granular carbides, γ＇-Ni3 A1 and MC. The microstructure in heat affected zone was the same as in the base metal, but grains in heat affected zone was bigger than in the base metal. The joint exhibited good high temperature properties with a tensile strength of 244 MPa at 927℃, as same as the base metal, and a creep life of 38.82 h at 927℃ and 62 MPa which was higher than the base metal. The fracture morphology of welded joints after high temperature tensile test and creep test were basically identical which were dimple and intergranular fracture, respectively.