| Abstract Scope |
With the increasing interest in space exploration and planet colonization, the research and advancement in producing components and repairing in space conditions through powder technologies have gained fundamental importance. Powder components in pressure-less sintering conditions ideally homogeneously shrink and retain their original shapes. However, sintering of real-world materials is influenced by many factors (e.g., temperature non-uniformity, friction forces, and gravity), which produce inhomogeneous densification and shape distortions in the final component. During sintering, non-uniform stress imposed by gravity influence the pore buoyancy, grain compression, and substrate friction, which affect the sintering densification, microstructure, properties, and dimensional uniformity. Ground-based and extraterrestrial sintering experiments on the liquid-phase sintering of tungsten heavy alloys are conducted, allowing to obtain densification and distortion data useful for extracting constitutive parameters needed to map the sintering response with and without gravity. It is shown that such models can enable predictions relevant to space-based repair and additive manufacturing. |