The effect of ultrasonic vibration on the current efficiency, crack density, microhardness, preferred orientation and microstructure of chromium plating was studied at frequency of 20 KHz.
Comparison was made between using constant ultrasonic field 145 watts and without ultrasonic field.
Cathodic current efficiency was decreased when the ultrasonic field was applied, which is due to increase in temperature and pressure from the formation of cavitation on the electrode surface. Crack density and microhardness were increased when the ultrasonic field was applied, which is due to increase in volume shrinkage and internal stress respectively. All the chromium deposits had a very strong <111> preferred orientation and columnar structure.
