EXISTENCE DOMAINS OF CONSUMABLE-ELECTRODE WELDING VARIETIES WITH ACTIVATING COMPOSITE ARGON COATING

Abstract

The activating composite halide salts-based coating effect on the existence domains of the argon welding varieties through the reversed polarity current is studied. The research has been conducted under the automatic beading on the plates of steel 20 with wire Sv-08G2S 1.2 mm d — both with the activating composite coating and without it. The activating composite coating (copper matrix with NaF, CaF₂ filler, and copper matrix with the dispersed phase mixture of NaCl + MgCl₂) was applied to the wire surface by electrolysis. The coating thickness was 20—25 microns. The welding electrical parameters (current and arc voltage) were recorded using a computer complex with the dual digital oscilloscope and “Diadem 10.1” program. The arc behavior and appearance (the arc shape), the droplet formation on the electrode wire, and metal transfer in the arc were recorded on the high-speed video camera (shooting speed was 2000 frames a second) synchronically with the welding electrical parameters recording. It is found that under the activating composite coated-wire metal welding, electric and physical parameters of the welding process are changing (the potential gradient of the arc column, the sum of the near-electrode voltage drops, efferscive of burn-off increase). The mode area with spray metal transfer expands towards the arc current decrease (lower feed rate), and the region with frequent shortcuts of the arc gap (similar to MAG) appears.