Amorphous and nanocrystalline Al82Ni10Y8 alloy powder prepared by gas atomization

Journal article, 2005

An Al-10Ni-8Y (at.%) alloy was atomized by Ar gas and the morphology, microstructure, thermal stability, phase composition and microhardness of the as-atomized powder were investigated. Most of the powders are spherical in shape, but the surface morphology was different for powder of different size. The cross-section microstructure of powder with size below 15 Pro in diameter showed no detailed feature, indicating existence of amorphous phase or nanocrystalline structure. The as-atomized powder showed four distinct exothermic peaks when heated at 296, 340, 366 and 456 degrees C. The glass transition temperature T-g, crystallization temperature T-x, and the temperature interval of the supercooled liquid region Delta T-x(=T-x-T-g) were detected to be about 266, 288 and 22 degrees C. The Al82Ni10Y8 alloy powder exhibits a high Vickers hardness of 230.6, and shows great potential for structural application. (c) 2004 Elsevier Ltd. All rights reserved.