不同超声频率电弧下316L焊缝的微观组织分析

Microstructure Analysis of 316L Welds under Different Ultrasonic Frequency Arc

摘要: 通过采用体式显微镜及EBSD（电子背射衍射）等手段对使用不同超声频率的316L不锈钢焊缝进行微观组织分析。结果表明，使用一定的超声频率电弧，能够减小焊缝柱状晶、增加等轴晶，当超声频率为60 kHz时，与普通TIG焊相比，焊缝柱状晶宽度细化程度达到58.6%，同时焊缝晶粒的细化程度可达35.6%，且焊缝金属晶界取向差增加，晶界稳定性更高，能够有效提升焊缝性能。

Abstract: The microstructure of 316L stainless steel weld by using different ultrasonic frequency arc assisted TIG welding was studied by means of stereomicroscope and EBSD. The results show that by using a certain ultrasonic frequency arc, the columnar grains of the weld can be reduced and the equiaxed grains can be increased.When the pulse frequency is 60 kHz, compared with that of the common TIG welding, the width of the weld columnar grains decreases by 58.6%, and the grain size of the weld decreases by 35.6%, and the grain boundary orientation difference of the weld metal is increased, and the grain boundary stability is higher.It effectively improves the weld performance.