The invention provides a
flash welding process of a high-strength low-magnetic anchor chain. The
flash welding process is characterized in that the burn-off degree reaches 7-9 mm, the
upset forging length reaches 6-8 mm, the burn-off speed reaches 1.8-2.0 mm / s, the secondary no-load
voltage reaches 4.7 V, and the
system pressure reaches 14-16 MPa. Compared with a conventional technological process, the
flash welding process has the advantages that a pre-flash process is added, so that the problems about the rapid heat dissipation of a material and the heating of welds during low-temperature
welding can be solved, the heat-affected area can be effectively enlarged, the
upset forging effect can be guaranteed, and the relatively consistent shapes of
welding joints can be guaranteed; sufficient
upset forging pressure is exerted on
welding end surfaces, gaps among the joints are rapidly reduced, the
lintel blasting is stopped,
liquid metal and
oxide inclusion on the end surfaces are extruded, and joint areas are subjected to certain plastic deformation, so that the progress of recrystallization can be promoted, common
crystal grains can be formed, and firm butt joints can be acquired; and after the upset
forging is finished, the pressure of electrodes and the pressure of an upset
forging oil cylinder are maintained for a certain time, and then the electrodes and the upset
forging oil cylinder are cooled, so that the deformation resistance of the joints can be sufficient and welding end ports can be protected against
cracking caused by ring-shaped springback.