低碳贝氏体钢的焊缝结晶裂纹敏感性研究

采用横向变拘束热裂纹试验方法（ＶａｒｅｓｔｒａｉｎｔＴｅｓｔ）对低磷贝氏体钢的焊缝结晶裂纹敏感性进行了研究。并与４２ＣｒＭｏ、３０ＣｒＭｎＳｉＡ钢作了对比．结合三种材料的结晶裂纹断口形貌讨论了化学成分和高温塑性对结晶裂纹敏感性的影响规律。结果表明，低碳贝氏体钢的结晶裂纹敏感性较小．导致这一结果的主要原因是由于低碳贝氏体钢焊缝中晶间低熔点偏析物较少，金属的高温塑性较好，因而具有较高的抗焊缝结晶裂纹的能力．

Study on Solidification Crack in Weld of Low-carbon Bainitic Steel

In this peper,transvarestraint test is used to invetigate the solidification crack susceptibility in weld oflow-carbon bainitic steel in comparison with 42 CrMo and 30CrMnSiA steels. The effects of chemical composition, high-temperature ductility on solidification crack susceptibility in the light of appearance of frcture ofsolidification crack in the three types of sted are discussed discussed. The results indicate that solidification crack sus ceptibility of low-carbon bainitic steel is less than other two steels. The dominant reason for the results is thatlow-melting intercrystaline segregaion product in weld metal of low-carbon steel is less and high tampertureductility of metal is nicer. With the result that the ability to resist solidification crack in weld of low-carbonsteel is higher.