摘要 |
PURPOSE:To provide a coated steel material prevented from corrosion due to hydrogen sulfide during the transport of oil or natural gas. CONSTITUTION:Cr, Mo or an alloy of them is applied to the surface of a plasma treated steel material in spots by plasma spraying and a powder of a thermoplastic resin such as PES, PEEK or PPS is applied to the coated surface of the steel material by electrostatic coating. As a result, the release of coating under hydrogen sulfide environment containing NaC and CO2 is prevented and excellent corrosion resistance is developed. |