Evaluation of Galvannealed Steel Sheet Produced by Zinc Vapor Deposition Process for Automotive Body Panel

Zinc-iron alloy coated steel sheet for automotive body panel has been developed. This newly developed sine-iron alloy coated steel sheet is produced in a continuous vapor zinc depositing, galvannealing and ferrous alloy electro-plating (plating of 4 g/m² as an upper layer only for outer panel) process at the Hanshin Works of Nisshin Steel Co., Ltd., Japan. This paper introduces the performances of this steel sheet; that is to say, the finishing quality of painting including cation type electro-coating, the corrosion resistance with and without paint coating, the weldability and the press formability. Through the tests, it was confirmed that this product possesses advantages of both conventional hot-dip galvannealed steel and zinc-iron alloy electro-plated steel and fully meets higher performance requirements for inner and outer panels of automotive bodies.