INFLUENCE OF SIZE AND SHAPE OF METALLIC SILVER AND PALLADIUM POWDERS ON THE AG70PD30 SOLID-SOLUTION FORMATION BY MECHANICAL ALLOYING

Silver-palladium solid solutions of composition Ag70Pd30 have been pro duced by mechanical alloying using, as metallic precursors, silver and palladium powders of different particle sizes and shapes prepared in our laboratory by the polyol process. The reaction kinetics as well as the morphologies of the final alloys are strongly dependent on the in itial particle size and shape of both the silver and palladium powders . This observation can be explained by considering that the initial st age of mixing is governed by an important particle-size effect.