Reduced Gravity and Microgravity Integrated Computational Materials Engineering (ICME)

This study seeks to motivate and focus NASA Biological and Physical Sciences (BPS) Division’s engagement within the broader Integrated Computational Materials Engineering (ICME) community to understand the phenomena underlying material processing, structure, and properties in the microgravity environment of space and to thereby support future space exploration efforts. Understanding the physical phenomena and properly capturing them in computational models will enable rapid advances in materials for both terrestrial and space use – for example, through better predictions of in-space joining, welding, and manufacturing. We have assembled a diverse, intermural team that connects NASA civil servants and contractors with external academic and industrial partners. A broad range of ICME-relevant disciplines are covered by this team, including but not limited to solidification simulations, thermodynamics and kinetics modeling, atomistic modeling, computational fluid dynamics, plasticity and process modeling, uncertainty quantification, thermophysical property measurements, structural and fracture mechanics, microgravity flight experiments on solidifying alloys, and advanced computing infrastructure. The team’s expertise and membership is not exhaustive but serves as a starting point to begin investigations of ICME with respect to BPS. This BPS ICME study group sought to survey the heritage & current flight experiments, current ICME engagement, and future opportunities concentrating on the BPS-relevant fields of thermophysical properties, solidification kinetics, coupled solidification-fluids, and structures up to the grain length scale (mesoscale). These fields were chosen as they represent the disciplines most relevant to metal alloys, which serve as a unifying theme throughout this report to assist the reader in understanding the links and other relations between flight experiments and ICME tools. The emergence of additive and in-space manufacturing gives emphasis to studies of rapid solidification in metal alloys. Certainly, other microgravity materials science themes are vital to study – for instance, semiconductor crystal growth, optical fiber drawing, etc. – but their inclusion is beyond the scope of this report. The study group also documented the required computational resources, elucidated scale bridging, and reviewed how uncertainty in this ICME framework can not only be quantified but also how uncertainty reduction via validation datasets is a raison d’etre for microgravity materials science – generating theory and physically validated computational models useful for understanding materials both in space and on the Earth.