Microstructure-Based Modeling for Life-Limited Components

Abstract

Abstract : The principle objective of the project was to bring together computational and experimental efforts in a comprehensive program to develop an integrated set of computational tools that would permit predictions of microstructural development and microstructure-based modeling of life-limited components in advanced titanium alloys (Ti-64 and Ti -6242). These computational tools are anticipated to significantly reduce extensive testing schedules and processing and inspection procedures, and permit development and insertion of new materials within acceptable costs and time frames. This AFOSR support underscored the activities of the Center for Accelerated Maturation of Materials (CA MM) at the Ohio State University (OSU). Significant progress has been made in integrating both experimental and computational efforts and different computational methods, ranging from CALPHAD thermodynamic modeling to phase field microstructure modeling, phenomenological equations, FEM crystal plasticity modeling and neural networks. The MEANS program involved graduate students and postdoctoral fellows in two departments (MSE and Mechanical Engineering) at OSU. Close and highly productive collaborations among the PIs have been established, leading to many publications in leading scientific journals. Moreover, strong interactions have been established between the MEANS and other on-going programs at CAMM, including the AFRL Metal Affordability Initiative (MAI) program and STW-21 program, and its industry partners. The outcomes of the project have made significant impact on developing and incorporating robust, predictive and physics-based materials models into new design philosophy for accelerated maturation and insertion of advanced titanium alloys. The major accomplishments are summarized bellow according to the three tasks, namely the modeling of fatigue in Ti-based alloys, microstructural modeling, and multi- time scale integration method for cyclic deformation in polycrystalline metals.