Kawasaki Steel Corporation

Junichi Mano

Masahiko Morita

Nobuo Totsuka

Minoru Nishida

Tomoo Tanaka

Masaki Mabuchi

Keizou Okuno

Syoichi Takizawa

Nobuo Aoyagi

Youzou Ogawa

The improved version of a chromated metal sheet has a chromate layer on at least one side of a metal substrate or a plated metal substrate and it is characterized in that the chromate layer has a chromium deposit of 10-200 mg/m.sup.2 per surface in terms of metallic Cr, that the chromate layer contains silica in an amount of 0.1-6.0 in terms of the weight ratio of SiO.sub.2 to Cr, and that the chromate layer contains at least one kind of lubricating particles selected from the group consisting of graphite, MoS.sub.2, BN, calcium stearate and an organic lubricating substance in an amount of 0.1-100 in terms of the weight ratio of the lubricating particles to Cr. The lubricating particles can have a surface layer capable of nonionic surface activating action, and this surface layer accounts for 1-70 wt % of the lubricating particles. The chromated metal sheet has sufficient lubricity to withstand press forming in the absence of lube oil coatings, has high enough electric conductivity to present no problems in spot weldability and groundability, and has sufficiently high corrosion resistance to withstand use in a naked state.

Chromated metal sheet having high corrosion resistance with improved

Method for producing hot-rolled steel sheets having a low yield ratio

Growing community of inventors

Tokyo, Japan

Junichi Mano