MANUFACTURE OF HIGH CORROSION RESISTANT VALVE FOR INTAKE AND EXHAUST VALVE FOR DIESEL ENGINE AND INTAKE AND EXHAUST VALVE

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacture of an alloy for an intake and exhaust valve for diesel engine, reduced in costs and excellent in corrosion resistance and strength, and the intake and exhaust valve. ;SOLUTION: The alloy has a composition consisting of, by weight, ≤0.1% C, ≤1.0% Si, ≤1.0% Mn, 25-32% Cr, 2.0-3.0% Ti, 1.0-2.0% Al, and the balance essentially Ni and containing, if necessary, either or both of ≤0.02% B and ≤0.15% Zr. At the time of manufacturing the valve for diesel engine by using the alloy stock with the above composition, the alloy stock is forged into a rough shape of valve and subjected to solid solution heat treatment and aging treatment and then partial cold working is applied to the valve face surface to partially increase the hardness of the valve face surface.;COPYRIGHT: (C)1998,JPO