Effects of process parameters on surface roughness and porosity for coatings deposited using the arc spray process

TWI Industrial Member Report Summary 430/1991

By M Amin

Background

Porosity produced in protective coatings deposited by the arc spray process is detrimental because it allows the corrosive liquids and gases to permeate to the substrate. The porosity level in the watings can be minimised by the judicious selection and control of the process parameters, as these are the key factors that determine the characteristics of the watings. In this study, the effects of the main parameters, including arc current, arc voltage, air pressure and standoff distance, have been determined on the porosity level and degree of surface roughness produced for aluminium-silicon coatings deposited on to a mild steel substrate.