| 摘要 |
An improved technique of pulsed-arc welding is described for applying, to a consumable welding electrode, a DC welding current on which is superimposed a cyclic, high-amplitude pulse component. The pulse-generating circuit includes a capacitor chargeable during the existence of the arc, such capacitor having a normally disabled discharge path including a first thyristor. Such thyristor is energized at a rate of 200-1,000 Hz from a trigger generator, which in turn is energized during the existence of the arc. The discharge pulses from the capacitor are coupled to the welding electrode via a pulse transformer whose secondary winding is isolated from the DC source via a blocking diode. The pulse-generating circuit is so designed that the pulses have a duration in the range of 0.5 x 10<->4 to 5 x 10<->4 sec., a front edge steepness greater than 8 x 106 amps/sec., and an amplitude selected so that the pulse current density through the welding electrode is greater than 720 amps/mm.
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