準結晶を含むガス噴霧Al-Cr系合金粉末の押出し成形と機械的性質

抄録

Bulk Al_96-xCr₃Ce₁Co_x(x=1, 1.5, 2) and Al_95-x Cr₃Ce₁Co_xTM₁(TM=Zr, Mn, Fe) materials with a dimension of about φ8 mm×300 mm were produced by extrusion of gas atomized powders at 523, 573, 623, 673 and 723 K. The gas atomized powder has a spherical shape with an average diameter of about 15μm, which consists of icosahedral, Al, Al₉Co₂ and Al₁₃Cr₂ phases. The bulk Al_94.5Cr₃Ce₁Co_1.5 material extruded at 573 K consists of icosahedral, Al, Al₉Co₂ and Al₁₃Cr₂ phases. The Yong's modulus, Vickers hardness (Hv), ultimate tensile strength and plastic elongation in the bulk form are 83 GPa, 170, 570 MPa and 8.4 % for Al_94.5Cr₃Ce₁Co₁₅ and 89 GPa, 210, 670 MPa and 4.4 % for Al_93.5Cr₃Ce₁Co_1.5Mn₁, respectively. The Hv at the testing temperature of 573 K for the Al_94.5Cr₃Ce₁Co_1.5 and Al_92.5Cr₃Ce₁Co_1.5Zr₂ bulk materials are 55 and 75, respectively, which are more than twice as large as that for the 7075-T6 alloy.