Arc characteristics and metal transfer behavior of twin-arc integrated cold wire hybrid welding

Abstract

Twin-wire arc served as a high-efficient technology has been fully developed and widely used in the manufacturing industry. In order to further increase welding deposition rate, a novel high-efficient welding system entitled twin-arc integrated cold wire hybrid welding was proposed in this paper. The study focuses on the effect of welding electrical parameters on alternative arcing and metal transfer process for the purpose of optimizing electrical parameters to realize a stable welding process. Characteristics of the metal transfer processes and the influence mechanism of welding electrical parameters on metal transfer modes were studied. The results showed that the two leading wires kept regularly alternative arcing with the phase difference of 180° between the pulse currents supplied to wires, and the alternating frequency increased with arc voltage and welding current. Besides, the metal transfer modes were divided into three types by varying welding parameters: short circuiting transfer, projected transfer, and streaming transfer. What is more important, the metal transfer mode highly depended on arc length, which was determined by arc voltage when welding current was kept constant. The metal transfer mode would change from short circuiting transfer to projected transfer, and then converted into streaming transfer eventually with the increase of arc voltage.