| Cast iron powder is prepared by pulverization of gay cast iron swarf (grade GC20) with conventional hammer mill. After degraphitization is carried out by extracting the free graphite flakes from the powder, the characteristics of green compacts and sintered products are studied. The results obtained are as follows; 1) The compactability of degraphitized cast iron powder is superior. When compacted between 8-l0ton/㎠ pressure, the green density of compact gets up to about 90% of its parent iron density. 2) The sintered density and green density of compacts are increased with increasing compacting pressure. 3) The strength of sintered product is increased with raising the compacting pressure and with increased sintering temperature and time. The tensile strength of the product compacted with 8ton/㎠ pressure and sintered at 1150℃, 90min in N₂＋3H₂atmosphere, goes up to 42.3㎏/㎟, twice of the tensile strength of its parent iron. |
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