OBTAINING OF Ni-Al INTERMETALLIC COMPOUNDS BY MECHANICAL ALLOYING

摘要

The study of the intermetallic compounds has been extensively pursued both at a fundamental and technological level for their remarkable high-temperature, high strength, and corrosion resistance properties. These compounds would be of even higher practical interest if their attractive high-temperature behaviour could be combined with good room formability. A possible route for obtaining of this feature might be the introduction of a substantial amount of disorder in their crystal lattices. Several techniques have been proposed for obtaining of a disorder state; laser-quenching, ion irradiation and mechanical alloying. Mechanical alloying is a technique which introduces a very large degree of structural damage and a high number of defects. An advantage of mechanical alloying over many other techniques is that it is a solid state technique and problems associated with melting and solidification are bypassed. The objective of the present work was to produce intermetallics of composites in the region of Ni-50 at.% Al and Ni-75 at.% Al with the aim of improving the possibilities of mechanical alloying application to the nickel alumides.