Abstract: The absence of gravity-dependent phenomena in microgravity allows an in-depth understanding of fundamental events that are normally obscured on earth. Of particular interest is that the low-gravity environment aboard the space provides a unique platform to synthesize alloys with homogeneous composition distributions and low defect concentrations, due to the much reduced buoyancy-driven convection and the easy realization of detached growth. Motivated by these facts, the materials science program in the SJ-10 recoverable scientific experiment satellite mainly focuses on the following issues: (i) the growth of ternary compound semiconductors with uniform composition and low defect density, (ii) solidification, defect control and interfacial phenomena of metal alloys, and (iii) the wettability of molten metal and preparation of metal matrix composites in space. The series of scientific experiments will be carried out successively in the same multiple materials processing furnace with precise controls on the sample position and the temperature gradient. We hope our program not only provides new sights into the crystal growth mechanism, but also guides the terrestrial crystal preparations.