The Inconel 690 alloy is widely used in the manufacturing of nuclear equipment, such as pipe welding for steam generators (SG) and pressure vessels, due to its excellent high-temperature strength, corrosion resistance, and thermal stability. However, coarse grains have been observed in the welded joint of Inconel 690. Considering its crucial role as a structural material under high pressure, temperature, and corrosive conditions, improvements should be made to the microstructure of the welded joint. The ultrasonic-assisted gas tungsten arc welding (UA-GTAW) was used in Inconel 690 welding. The influence of ultrasonic vibration on the microstructure and mechanical properties of welded joints was studied. The results show that the ultrasonic refined the microstructure further to improve the mechanical properties. The UA-GTAW sample performed superiorities over regular GTAW joint in multi perspective including refined solidification grains, less element segregation, higher tensile strength and hardness. The Yield strength, ultimate tensile strength, and elongation increased from 320 MPa, 591 MPa, and 25.1 % to 387 MPa, 672 MPa, and 31.6 %, respectively.

中文翻译：

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Inconel 690合金的超声波振动辅助钨极氩弧焊：超声波作用细化晶粒，提高机械性能


Inconel 690合金因其优异的高温强度、耐腐蚀性和热稳定性而被广泛应用于核设备的制造，例如蒸汽发生器（SG）和压力容器的管道焊接。然而，在Inconel 690的焊接接头中观察到粗晶粒。考虑到其在高压、高温和腐蚀条件下作为结构材料的关键作用，应对焊接接头的显微组织进行改进。 Inconel 690 焊接采用超声波辅助钨极氩弧焊 (UA-GTAW)。研究了超声振动对焊接接头显微组织和力学性能的影响。结果表明，超声波进一步细化了显微组织，提高了力学性能。 UA-GTAW样品在多个方面均优于常规GTAW接头，包括细化的凝固晶粒、更少的元素偏析、更高的拉伸强度和硬度。屈服强度、极限抗拉强度和伸长率分别从 320 MPa、591 MPa 和 25.1% 增加到 387 MPa、672 MPa 和 31.6%。