Fabrication of nano-particulate composites in Bi-Al and Pb-Al systems by bulk mechanical alloying

Neither conventional melting/solidification and powder metallurgy nor mechanical alloying by ball-milling mechanical alloying processes are suitable to fabrication of bulk alloy materials with significant differences in melting temperature and density of mass; hence, microgravity alloying is selected and used to yield bulk solids in Bi-Al and Pb-Al systems. In the present paper, superiority to our developed high speed mechanical alloying for these material systems is theoretically discussed by using the Navier-Stokes equations. Both Bi-Al and Pb-Al systems are employed to demonstrate experimentally that homogenization and refining should take place with the number of cycles in the present mechanical alloying.