Abstract In this study, the phenomenon of gas removal behaviors in the melt pool and the flow behaviors of melt pool were observed using an in-situ X-ray imaging method. Based on the ultrasonic effects, a novel processing method was developed to reduce porosity and decrease diffusible hydrogen content in the deposited metal. The effects of ultrasonic output power on the size and frequency of gas bubble collapsing were studied. Results showed that with the assistance of ultrasonic, the gas bubble size were smaller and the collapsing frequency was significantly increased. The porosity decreased from 1.4% to 0.5% and the hydrogen diffusible content decreased from 24.5 to 18.6 ml/100 g when the ultrasonic power increased to 720 W. The possible hydrogen removal mechanism was proposed by two aspects including the microcosmic and macrocosmic scale.

中文翻译：

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超声波在水下湿焊中增强熔体脱气和除氢的原位观察

摘要 本研究采用原位X射线成像方法观察熔池中的除气现象和熔池的流动行为。基于超声波效应，开发了一种新的处理方法，以减少沉积金属中的孔隙率和扩散氢含量。研究了超声输出功率对气泡破裂大小和频率的影响。结果表明，在超声波的辅助下，气泡尺寸变小，崩溃频率显着增加。当超声功率增加到720 W时，孔隙率从1.4%下降到0.5%，氢扩散含量从24.5下降到18.6 ml/100 g。从微观和宏观两个方面提出了可能的脱氢机制。