The influence of gravity on composition uniformity and microstructure in immiscible Al-In alloys.
The results obtained from flight experiments on hypermonotectic Al-In alloys carried out during the Life and Microgravity Spacelab mission are presented and compared to those predicted from models that have been developed for solute redistribution in eutectic alloy systems. Experimental results from microgravity experiments are also compared with results obtained from unit gravity directional solidification experiments. Unit gravity directional solidification of hypermonotectic alloys results in macrosegregation due to convective instability inherent in these alloy systems. Identical samples directionally solidified under microgravity conditions reveal a much more uniform composition profile. Results indicate steady-state coupled growth is possible in hypermonotectic alloys through microgravity processing.
Andrews
J Barry
JB
Materials Science and Engineering Department, University of Alabama at Birmingham, 35294-4461, USA. bandrews@eng.uab.edu
Hayes
Letitia J
LJ