Study on Digital Magnetic Control Power Supply for Deep Penetration K-TIG Assisted Welding and Toughening Mechanism

doi:10.3901/JME.2025.18.086

Abstract

Abstract: In order to tackle problems like large heat input and low impact toughness of the welded joint in Keyhole Tungsten Inert Gas (K-TIG) welding, an alternating magnetic field with longitudinal direction for K-TIG welding was proposed in this research. The characteristics of the excitation coil were analyzed, and a digital magnetic control power supply was developed. The newly developed magnetic control power supply boasts the capability to output a broad spectrum of frequencies and amplitudes, featuring a high power factor and a soft-switching working state for the MOSFET. By inducing an external longitudinal alternating magnetic field with sinusoidal changes in intensity and direction, the K-TIG welding arc rotates and agitates the weld pool, leading to a significant reduction in penetration current. Moreover, since there is a 14.5% reduction in heat input compared to K-TIG welding without magnetic assistance, the grains in the welding joint are refined, and the impact toughness of the welded joint is enhanced by up to 96%. At the same time, tensile strength is also improved to a certain extent.

Key words: magnetic control power supply, K-TIG, digital control, gain refine, alternating magnetic field

CLC Number:

TG439

ZHAN Jiatong, SHI Yonghua, LIU Zhizhong, YE Xiongyue, LIANG Zhuoyong. Study on Digital Magnetic Control Power Supply for Deep Penetration K-TIG Assisted Welding and Toughening Mechanism[J]. Journal of Mechanical Engineering, 2025, 61(18): 86-97.

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