| abstract |
There is provided an iron-based powder compositionnfor powder metallurgy excellent in flowability andncompactibility. The iron-based powder composition for powdernmetallurgy is produced in accordance with a method comprisingnthe steps of: adding to iron-based and alloying powders, forna primary mixing, a surface treatment agent, and in addition,nfor a secondary mixing, a fatty acid amide and at least onenlubricant, wherein the lubricant has a melting point highernthan that of the fatty acid amide and is selected from thengroup comprising, a thermoplastic resin, a thermoplasticnelastomer, and inorganic or organic compounds having layeredncrystal structure; heating and stirring up a mixture afternthe secondary mixing at a temperature over a melting pointnof the fatty acid amide to melt the fatty acid amide;ncooling, while mixing, the mixture subjected to the heatingnand stirring process so that the alloying powder and anlubricant having a melting point higher than the fatty acidnamide adhere to a surface of the iron base powder subjectednto the surface treatment by an adhesive force of the melt;nand adding at time of the cooling, for a tertiary mixing, anmetallic soap and at least one type selected from a groupncomprising thermoplastic resin or thermoplastic elastomer npowders and inorganic or organic compounds having layeredncrystal structure. The mixture is heated to about 423K andnloaded into a die for compaction. |