| 摘要 |
PROBLEM TO BE SOLVED: To produce high strength powder sintered parts having excellent strength as-molded and fired by using pure iron powder and silicon carbide powder and specifying the particle size of the above powder bodies, blending ratios thereof and the firing temp. SOLUTION: By weight, 15 to 30% silicon carbide powder and 70 to 85% pure iron powder having 1 to 100μm particle size are added with 0.1 to 1.5% zinc stearate as a binder, and they are mixed and molded. This molded body is fired at 1050 to 1300 deg.C in a reducing or vacuum atmosphere. Thus, the iron powder 1 and silicon carbide powder 2 at the time of molding are metallically bonded, simultaneously, the silicon carbide is separated into carbon and silicon, and they are respectively diffused into the spaces of the iron powder, by which a region 7 of iron composed of cementite and ferrite and carbon and an iron base region 8 contg. silicon are formed. Thus, the part present as the molded body compsn. as it is shown in the conventional powder molded body is made small, and the objective powder fired parts can be obtd.
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