Research on self-propagating high-temperature synthesis welding for wire connection

Abstract A new method of non-electric welding based on self-propagating high-temperature synthesis (SHS) technology for reliable and efficient connection of cable breakage has been proposed. The principle of wire SHS welding has been elucidated, the composition of the welding flux has been optimized, and the welding mould and special fixture have been designed. Welding tests have been carried out, and the performance has been studied. It was shown that the broken wire could be welded reliably and efficiently by SHS welding. The appearance of the joint was perfect, and there were no inclusions, pores, cracks, pits, or other obvious defects in it. Micromorphology analysis suggested that the matrix of the joint metal was an α-copper solid solution with granular iron-rich second phase dispersedly on it. Performance tests found that the tensile strength of SHS welded wire was above 280 N/mm 2 , the average Vickers hardness of the weld joint was 206, the average impact toughness was 33.3 J/cm 2 , and the average resistivity was about 1.58×10 −7 Ω·m, which meets the emergency maintenance needs. Research showed that SHS welding does not require external energy and complex equipment, it is simple to operate and easy to carry, and the joint has favourable performance; the broken wire could be welded reliably and efficiently. It is an ideal method for cable maintenance in an emergency.