Abstract
We carried out a microgravity experiment -Mixing of Melt of Multicomponent of Compound Semiconductor- conducted aboard the Second International Microgravity Laboratory (IML-2) Space Shuttle mission in 1994. Six types of samples, which are composed ofln-Sb (M-1, D-1) and In-GaSb-Sb (M-2, M-3, M-3', D-2), were melted and solidified. M-samples (M-1, M-2, M-3, M-3') and D-samples (D-1, D-2) were mixed by Marangoni convection due to concentration gradient and molecular diffusion only, respectively. The concentration profiles were measured by Electron Probe for Micro Analysis (EPMA) . IML-2 samples show more uniform distribution than ground samples because the buoyancy convection and gravity segregation can be suppressed under microgravity. Moreover, the experimental fact that the M-samples were more uniform than D-samples reveals that the Marangoni convection enhanced the mixing of melt. Numerical simulations also justified the quick mixing by the solutal Marangoni convection.
