| 摘要 |
PURPOSE:To improve corrosion resistance, strength and wear resistance by a method wherein the corrosion resistance to hydrofluoric acid is nearly equal to Hastelloy and nozzles are used which is stronger in precipitation hardening than HRC36. CONSTITUTION:Solution heat treatment is given to the bar material of alloy composed of 0.05-0.20% C, 0.5% or lower Si, 1.0% or lower, 4.0-22% Cr, 8.0-12.0% Co, 8.0-12.0% Mo, 0.75-1.5% Al, 2.0-3.0% Ti, 5.0% or lower Fe and the residue composed of Ni and impurities, in weight %. An article of a specified form is manufactured from the bar material and then precipitation hardening HRC36 or higher is given and aging to the article at about 760 deg.C. The above-mentioned main component has the following functions. C exists in austenite in the form of solid solution and generates carbide with Cr, Mo, Ti, etc. Si is added as deoxidizer, Mn also is added as deoxidizer and improves hot working properties. Cr improves corrosion resistance and oxidation resistance properties. Co improves corrosion resistance, heat resistance and accelerates precipitation hardening. Additionally, Mo improves corrosion resistance, increases strength at ordinary and high temperature. |
