SA-204Gr.C的焊接性能与金相组织

Welding Properties and Metallographic Composition of SA-204Gr.C

通过碳当量、冷裂纹敏感系数、热裂纹敏感系数和再热裂纹系数对SA-204 Gr.C进行焊接性分析,根据分析采取合理的措施,采用埋弧焊和焊条电弧焊对SA-204 Gr.C碳钼钢进行焊接。对焊接接头进行无损检测,未发现裂纹、气孔、夹渣等缺陷;对焊接接头进行横向拉伸、纵向拉伸、弯曲、冲击等力学性能试验,结果均满足标准和项目要求;分析焊接接头的显微组织,焊缝组织为铁素体和贝氏体,热影响区为铁素体、贝氏体和珠光体。试验结果表明,采用合理的措施和合适的焊接参数,使用埋弧焊和焊条电弧焊均能获得优异焊接接头,并成功应用于产品焊接。

With the properties of carbon equivalent, cold crack sensitive factor, hot crack sensitive factor and reheating crack factor, the weldability analysis of SA-204Gr.C was performed. Based on the analysis result, appropriate welding procedures with SMAW and SAW were used for the joint with base material of SA-204Gr.C. In later nondestructive test, there is no crack, gas cavity or inclusion found. Then, for this weld joint, transverse tensile, longitudinal tensile, bending and impact tests were carried out, and the results of the all tests were satisfied with the requirements in standards and project specifications. From the analysis of micro-composition of the weld joint, it was found that in welding seam there were ferrite and bainite and in heat affected zone there were ferrite, bainite and pearlite. From the result of test, it was shown that if appropriate measures and welding parameters were selected, whatever with use of SMAW or SAW, good quality of weld joint can be obtained.