Abstract: The present invention relates to a dual-layer sintered valve seat ring having high stiffness and strength. The features of such ring are: fusion infiltration of Cu into the pores of a ferrous sintered body; hard alloy particles dispersed in the matrix of the valve seat body; the composition of the base and the ferrous sintered body; high density; and, diffusion of an alloying element of the hard particles around them and into the matrix.

Abstract: A sintered powdered ferrous alloy article having high heat and abrasion resistances and a high workability is produced by admixing, (1) 5 to 30% by weight of a finely divided component alloy which consists of the following composition,______________________________________ 1 to 4% by weight carbon 10 to 30% by weight chromium 2 to 15% by weight nickel 10 to 30% by weight molybdenum 20 to 40% by weight cobalt 1 to 5% by weight niobium the balance iron, ______________________________________(2) 0.8 to 2% by weight of finely divided carbon and (3) the balance of a finely divided ferrous base metal, compression molding the admixture under a pressure of 4 to 6 metric tons/cm.sup.2 and sintering the molded admixture in a reducing atmosphere at a temperature of 1050.degree. to 1150.degree.