Integrated Computational Materials Engineering (ICME) for In-Space and Extraterrestrial Surface Metal Welding and Joining

Despite the maturity of welding and related joining processes for terrestrial applications, there is limited understandingnbsp;nbsp; of the effects of an in-space environment on weld quality. An Integrated Computational Materials Engineering (ICME) framework leveraging physics-based process and metallurgical models , anchored by terrestrial and flight data, is desired to predict the effects of in-space, lunar, and Martian environments on the welding process and resulting material properties. To address this need, CFD Research will establish critical elements of such a framework, namely physics-based welding process models to evaluate the relevant environmental effects (microgravity, vacuum, extreme ambient temperature), and grain structure evolution models addressing both fusion from the melt and coarsening in the heat affected zone. nbsp; During the Phase I effort, models for evaporation effects on the weld melt pool were evaluated and a compact, efficient approach to incorporating these effects into multiphysics welding process simulations was developed. Additional model components necessary for such simulations to address in-space laser welding were identified, and weld pool state information was used to predict the solidification microstructure. In this Phase II effort, CFD Research will adapt and validate software to fill the remaining gaps in an ICME framework for in-space welding process developers, establish data transfer to link melt pool scale welding simulations with prediction of the resulting grain structure, and validate the linked software against historical and upcoming flight data. Application studies will be performed to develop and mature the simulation and analysis workflow, followed by documentation and delivery of the resulting software and test cases to NASA.