MECHANICALLY SYNTHESIS AND MECHANICAL PROPERTIES OF NANOCRYSTALLINE INTERMETALLICS NiAl
GUO Jianting; ZHOU Lanzhang; LI Gusong(Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110015)Correspondent: GUO Jianting, professor, Tel: (024)23845551-55493, Fax: (024)23891520,E-mail: jtguo@imr. ac. cnManuscript received 1999-04-
Nanocrystalline NiAl has been synthesized by mechanical alloying elemental powders and hot pressing, its microstructure and mechanical properties have been investigated. The results show that the reaction mechanism of NiAl during milling can be attributed to explosive reaction induced by mechanical collision. Compacts of nanocrystalline NiAl with near full density have been achieved by hot pressing the drilled powder. The nanocrystalline NiAl material is much strong and ductile over cast and extruded NiAl at room temperature. Yield strength of the nanocrystalline NiAl at high temperature is dependent on strain rate, and deformation is considered to be controlled by diffusion mechanism.