Method of surface treatment of aluminum killed steel in preparation for porcelain coating

摘要

A surface treatment process for parts fabricated of aluminum killed steel in preparation for porcelain coating wherein the parts are subjected to a plurality of sequential liquid spraying treatments as follows: (1) An aqueous alkaline cleaning solution at a temperature of about 180 DEG F. (about 82 DEG C.); (2) A first water rinse; (3) An aqueous ferric sulfate solution having a concentration of from about 0.5% to about 1% and a temperature of from about 155 DEG F. to about 160 DEG F. (about 68 DEG C. to about 71 DEG C.); (4) A second water rinse; (5) An aqueous sulfuric acid solution having a concentration of about 2.5% and a temperature of about 140 DEG F. (about 60 DEG C.); (6) A third water rinse; (7) An aqueous nickel sulfate solution having a nickel concentration of from about 2 to about 2.5 oz./gal. and a temperature of about 150 DEG F. (about 65 DEG C); (8) An aqueous sulfuric acid solution having a concentration of about 0.35% to about 0.45% and a temperature of from about 130 DEG F. (54 DEG C.) to about 140 DEG F. (60 DEG C.); (9) An alkaline neutralizer spray; and (10) A fourth water rinse the final portion of which is with deionized water.