电子束焊对TA1中厚板微观组织及力学性能的影响

Effect of EBW on microstructures and mechanical properties of TA1 medium plate

采用电子束焊对30 mm厚的TA1板开展焊接试验,通过对接头进行宏观与微观组织观察与分析、维氏硬度、拉伸及冲击试验,研究了焊接过程对TA1微观组织及力学性能的影响。结果表明,焊接接头综合力学性能优良。在焊接热循环作用下,接头不同区域的微观组织差异显著:TA1中厚板母材组织为等轴α;焊缝为由α柱状晶、锯齿α和少量针状α组成的混合组织;热影响区组织为锯齿α。与母材相比,电子束焊使得接头焊缝及热影响区的强度、硬度及冲击韧性均有明显提高。

TA1 medium plate with a thickness of 30 mm had been welded by applying electron beam welding(EBW). The effect of the welding process on microstructures and mechanical properties of TA1 medium plate had been investigated with the testing measures,such as macrostructure and microstructure observation and analysis,Vickers hardness,tensile test and impact test. The test results showd that the welded joint possesses excellent comprehensive mechanical properties. Under the effect of welding thermal cycles,notable microstructure differences existed in different areas of the joint. The base metal was composed of equiaxed alpha. The weld seam was composed of a hybrid microstructure,including alpha columnar crystal,serrated alpha and a bit of acicular alphas. The heat affected zone was made up entirely of serrated alpha. Compared with base metal,electron beam welding made the strength,hardness and impact toughness of the weld seam and heat affected zone exhibited significant improvements.