METHOD AND APPARATUS FOR ELECTRIC SPARK ALLOYING Russian patent published in 2001 - IPC

FIELD: electric-erosion working processs, possibly for improving quality of tool and machine parts. SUBSTANCE: method comprises steps of applying ultrasonic oscillation onto alloying electrode; supplying direct current pulses along path of approaching electrode and part in time moment of decreasing offset of ultrasonic oscillations of electrode until threshold value. Apparatus includes acoustic oscillation system with alloying electrode in its end portion and generator of electric current for driving acoustic system. Positive pole of direct current pulse generator is connected with alloying electrode, negative pole, with worked part. In front of alloying electrode pickup is arranged. Signal of said pickup is proportional to offset value of ultrasonic oscillation of electrode. Through transistorized switching unit, unit for differentiating rectangular pulses and frequency divider pickup is connected in series with direct current pulse generator. Method and apparatus allow to receive coatings with thickness of layer up to 500 micrometers at rate 10-50 sq.cm/min and with roughness of coating layer determined according to parameter of arithmetic mean Ra = 2.5-0.32 micrometers. EFFECT: enhanced wear resistance, corrosion resistance of parts. 4 cl, 2 dwg, 1 ex