A new class of materials, called hierarchical materials, characterized by microstructure rich in features with different length scale, showing revolutionary properties, has emerged recently in multiple application areas, especially in the additive manufactured metals and alloys. Similarly, recent advancement in process control abilities and novel manufacturing technologies have demonstrated great potential to tailor microstructural evolution. Together these two recent developments offer ability to derive hierarchical materials with tailored microstructure; a promising pathway to engineer/design materials with remarkable properties. The lack of microstructure informed computational model to serve as material/component design tools is a critical gap in the field that the proposed research is intend to fill.
In this Phase I proposal, we propose a computational model to predict mechanical properties of metals and alloys with hierarchical microstructure using generalized method of cells (GMC) on NASA’s FEAMAC/GMC platform. The proposed building of multiscale model involves two major innovations: 1) an advancement of the crystal plasticity based constitutive modeling framework from its current limited ability to model simple microstructure consisting of single crystal, poly-crystal and/or precipitation hardened metal alloys to hierarchical microstructure that consists of microstructural features of various length scales; a transformational step in the field of elastic-plastic constitutive modeling topic area, and 2) two new testing methods for characterizing elastic-plastic mechanical properties at microstructural length scales; a transformational step in the mechanical testing of materials that could enrich the multiscale model development and validation. In addition, proposed Phase I project extends the application of FEAMAC/GMC multiscale framework to a very different class of materials from its traditional composites and ceramics based material systems applications
Development of metal and metallic alloys with excellent mechanical properties is extremely important for both the aerospace and aeronautical applications. For future aircraft with hybrid electric or all electric propulsion systems, advanced materials technology is needed for power components including electric machines and power cables. The proposed innovation has the potential to make positive impact on all important NASA missions and programs.
The proposed multiscale model with microstructure informed constitutive model will be a powerful useful computational tool in the the field of additive manufacture. It can be used as: 1)accurate stress analysis tool for built structural components, 2) process optimization tool that can yield optimal mechanical properties, 3) a powerful tool for realizing "material by design concept"