Patent Number: 6,305,666

Title: Valve seat made of Fe-based sintered alloy excellent in wear resistance

Abstract: A valve seat made of Fe-based sintered alloy, the Fe-based sintered alloy comprising, on a weight percent basis: calcium fluoride: 1-15%, with the balance Fe and the inevitable impurities, wherein the Fe-based sintered alloy has a structure in which Co-based alloy hard particles A, which comprise Co--Mo--Cr alloy and have high temperature wear resistance, and Cr-based alloy hard particles B, which comprise Cr--W--Co--Fe alloy and have ordinary temperature wear resistance, are dispersed and distributed in the alloy steel base in a total amount of 6-26 area percent when they are observed on a structural photograph recorded by an optical microscope, wherein, in the alloy, the ratio of hard particles A to total hard particles is 25-75 area percent, and wherein the calcium fluoride particles are dispersed and distributed in the alloy steel base in an amount of 3-45 area percent, and the Fe-based sintered alloy has a porosity of 5-25%, said valve seat having excellent in wear resistance.

Inventors: Sakai; Masaaki (Niigata, JP)

Assignee: Mitsubishi Materials Corporation

International Classification: C22C 33/02 (20060101); C22C 38/44 (20060101); C22C 38/52 (20060101); C23C 10/28 (20060101); C23C 10/00 (20060101); F01L 3/02 (20060101); C22C 033/02 (); C22C 038/42 (); F16K 051/00 ()

Expiration Date: 10/23/2018