US Patent 11988294 Sintered valve seat insert and method of manufacture thereof

A powder admixture useful for making a sintered valve seat insert includes a first iron-base powder and second iron-base powder wherein the first iron-base powder has a higher hardness than the second iron-base powder, the first iron-base powder including, in weight percent, 1-2 % C, 10-25 % Cr, 5-20 % Mo, 15-25 % Co, and 30-60 wt. % Fe, and the second iron-base powder including, in weight %, 1-1.5 % C, 3-15 % Cr, 5-7 % Mo, 3-6 % W, 1-1.7 % V, and 60-85 % Fe. The powder admixture can be sintered to form a sintered valve seat insert optionally infiltrated with copper.