The NiCr rustless steel null which improves corrosion resistance and machinability

摘要

PURPOSE:To improve corrosion resistance and machinability, by specifying the components and contents of an Ni-Cr stainless steel and particularly adding specific amounts of Sn. CONSTITUTION:An Ni-Cr stainless steel has a composition consisting of, by weight, =0.08% C, =1.0% Si, =0.7% Mn, =0.04% P, =0.005% S, 8.0-12.0% Ni, 17.0-20.0% Cr, 0.40-0.80% Mo, =0.3% Cu, 0.03-0.5% Sn, and the balance Fe. The Sn added improves not only machinability but also general corrosion resistance and crevice corrosion resistance. Particularly in an aqueous solution of dilute sulfuric acid, Sn is precipitated at the steel surface to increase hydrogen overvoltage and, as a result, sulfuric-acid resistance is improved. This stainless steel can be suitably used as a material particularly for flatware apparatus.