Vibration Surfacing

or vibroarc surfacing, the coating of surfaces by means of a vibrating consumable electrode (for example, steel wire); it is a variant of the welding process. The tip of the electrode touches the surface of the workpiece, shorting the welding circuit. When the electrode moves 1.5-3 mm away from the surface, the circuit is broken and a spark, or electric arc, occurs. This process is repeated at regular intervals at a frequency of approximately 100 Hz. The area of deposition is continuously irrigated by aqueous solutions of salts or glycerin and is sometimes sprinkled with a granular flux. Vibration surfacing is used mainly in repair work to face axles, rolls, hydraulic turbine blades, and other steel parts, as well as in the manufacture of bimetallic parts (involving the coating of steel, cast iron, and other metals with nonferrous metals and alloys). The quality of the metal deposited is poor, but it is extremely hard and highly wear-resistant without heat treatment.