| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a powder forged member in which fatigue strength is improved while securing its machinability without increasing its hardness, and self-compatibility after a fracture split can be secured, to provide a powdery mixture for powder forging, to provide a method for producing a powder forged member, and to provide a fracture split type connecting rod using the powder forged member. <P>SOLUTION: The powder forged member having excellent machinability and fatigue strength is obtained by forging a sintered preform formed by subjecting a powdery mixture to preliminary compacting and thereafter sintering the same at high temperature. The ratio of free Cu in the sintered preform upon the start of the forging is ≤10%. Further, its componential composition after the forging is composed of, by mass, 0.2 to 0.4% C, 3 to 5% Cu and ≤0.4%(excluding zero) Mn, and the balance iron with inevitable impurities, and also, a ferrite ratio therein is 40 to 90%. <P>COPYRIGHT: (C)2008,JPO&INPIT |
