摘要 |
An AlN dispersed powder aluminum alloy with a particular composition and structure has excellent wear resistance, seizure resistance, heat resistance, toughness and machinability. In the structure of the alloy, AlN layers are discontinuously dispersed along some of the grain boundaries of former aluminum alloy particles in the matrix of an aluminum alloy sintered body. Diffusion and sintering progresses between non-nitrided grains at areas of grain boundaries not having AlN layers, to attain strong bonding between the grains. A nitriding accelerative element such as Mg, Ca or Li is provided in some of the grains to promote the discontinuous formation of the AlN layers. Additionally, layers of a nitriding suppressive element such as Sn, Pb, Sb, Bi or S may be discontinuously dispersed at regions along some of the grain boundaries, and bonding between grains is achieved at these regions as well. The alloy is prepared by sintering a green powder compact of prescribed composition under prescribed sintering conditions.
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