Title: Tin-free steel strips useful in the mfr. of welded cans and process for making
Application Number: 86102555 Application Date: 1986.03.14
Publication Number: 1005911 Publication Date: 1986.12.17
Approval Pub. Date: 1991.06.19 Granted Pub. Date: 1991.06.19
International Classifi-cation: C25D3/04;C25D5/12
Applicant(s) Name: Kawasaki Steel Corp. Address:
Inventor(s) Name: Hajime Ogata;Hisatada Nakakouji;Yasuhiro Akeda
Attorney & Agent: YANG LIQIN
Abstract:
    A tin-free steel strip comprising a steel strip, 40 to 150 mg/m2 of a metallic chromium layer on the steel surface, and 5 to 25 mg/m2 of a chromium compound containing layer thereon wherein the metallic chromium layer contains a plurality of protrusions, exhibits improved corrosion resistance and weldability and is thus useful in the manufacture of welded cans. The tin-free steel strip is produced by chromium plating a steel strip in an aqueous solution containing CR6 preferably to a weight of 40 to 140 mg/m2, subjecting the chromium plated strip to anodic electrolysis, preferably at an eectricity quantity of 0.1 to 10 C/dm2, and subjecting the strip to a cathodic treatment in an aqueous solution containing Cr6 and a chromium plating aid so as to deposit additional metallic chromium, preferably in a weight of 10 to 60 mg/m2.
Time: 3