Microstructure analysis of samples sintered at different gravitational conditions

Tungsten heavy alloy samples liquid phase sintered under normal gravity and microgravity conditions are examined in this study for microstructure, phase, grain orientation, and lattice misorientation comparison. The focus is on understanding gravitational effects on the microstructure evolution as a function of location in the samples sintered using different holding times. This analysis shows that gravity has sub-grain level effects. The main differences are observed at the grain boundaries and in the relative orientation of the touching grains. Microgravity sintering is conducive for solid grain rotation into low lattice misorientation angle arrangement and potentially coalescence.