焊接位置对药芯焊丝熔敷金属低温冲击韧性的影响

摘要

Effects of vertical up and flat welding positions on the microstructure and low temperature impact toughness of deposited metal of E81T1-K2 flux cored wire (FCW) were studied according to ANSI/AWS A5. 29 ?1998 standard. The results show that the low temperature impact toughness of deposited metal in vertical up welding position was 65 ?71 J higher than that of in flat welding position which was 39 ?46 J. The ratio of columnar grains in deposited metal formed in vertical up welding was less than that in flat welding, but the width was in the contrary situatioa More acicular ferrite can be obtained in the deposited metal in vertical up welding. Compared with the deposited metal formed in flat, the inclusions were much smaller and more uniform in deposited metal formed in vertical up welding, which was beneficial for the nucleation of acicular ferrite.%根据ANSI/AWS A5.29-1998标准,采用不同的热输入研究了E81T1-K2药芯焊丝平焊和立向上焊接(立焊)位置对熔敷金属组织和低温冲击韧性的影响.结果表明:立焊得到的熔敷金属的低温冲击吸收功为65～71 J,高于平焊熔敷金属的(39～46 J)；立焊熔敷金属中柱状晶比例小于平焊位置的,但其宽度较大,含有更多尺寸细小的针状铁素体；立焊熔敷金属中的夹杂物更均匀细化,尖锐度较小,有利于针状铁素体的形核.