稀土氧化钇对高强度钢焊条熔敷金属组织和性能影响

基于Ni-Cr-Mo-V合金体系,研究了稀土氧化钇对800 MPa高强度钢焊条焊缝微观组织和性能的影响.结果表明,Y₂O₃含量在0~0.02%范围内变化时,随着Y₂O₃含量的增加,焊缝熔敷金属组织中先共析铁素体逐渐降低,针状铁素体含量逐渐增加,强度和低温冲击韧性均逐渐增加,且当Y₂O₃含量为0.02%时,焊缝熔敷金属低温冲击韧性达到最大值;当Y₂O₃含量超过0.02%时,焊缝熔敷金属组织中针状铁素体含量下降,低温冲击韧性降低.综合考虑上述因素,该高强度钢焊条中Y₂O₃最佳添加量为0.02%左右.

Effect of yttrium oxide on microstructure and mechanical properties of in high strength steel weld metal

Based on Ni-Cr-Mo-V alloy system, the effect of yttrium oxide on microstructure and mechanical properties of weld made with 800 MPa high strength steel electrode was investigated. Experimental results show that, as the Y₂O₃ content changed in 0~0.02%, with the increase of Y₂O₃ content, the proeutectoid ferrite content reduced, the acicular ferrite content increased, and the strength and low-temperature impact toughness increased gradually. When the Y₂O₃ content was 0.02%, the low-temperature impact toughness of weld metal reached the maximum. When the Y₂O₃ content was over 0.02%, the acicular ferrite content in the weld reduced, and the low-temperature impact toughness decreased. Therefore, the optimum Y₂O₃ content for high strength steel electrode is about 0.02%.