Surface Treatment of Cold Rolled Steel by Phosphating

Abstract The effect of surface treatment on the kinetics of phosphating cold rolled steel (CRS) has been investigated. Scanning electron micrographs revealed different surface structures after chemical treatments. CRS etched with HCI gave the fastest rate as well as a higher weight of phasphate coating. A heated (oxidized) surface retarded the rate of phosphate deposition up to ten-fold. The strength of the phosphate layers deposited on CRS surfaces were calculated to be from 4.2 to 5.8 × 102 kN m−2.