Patent ID: 11951547
Assignee: TPR CO., LTD.
Field: Materials, metallurgy (Chemistry)
Classification: CPC B  C  F | IPC B  C  F

Claim 2:
3. A method of producing a valve guide made of an iron-based sintered alloy, the method comprising the steps of:
molding raw material powder including a diffusion-alloyed powder consisting of core iron powder and Cu bonded to the core iron powder through diffusion to obtain a molded body, and
sintering the molded body, to thereby produce a valve guide made of an iron-based sintered alloy,
(1) the raw material powder having a content of a Cu component falling within a range of from 24.2 mass % to 35 mass %,
(2) a ratio of a Cu component derived from the diffusion-alloyed powder consisting of core iron powder and Cu bonded to the core iron powder through diffusion with respect to the Cu component contained in the raw material powder being 45% or more; and
wherein the valve guide has a thermal conductivity at 400° C. of about 50 W/m·K to about 55 W/m·K.