| 摘要 |
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.
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