Discovery, Development and Deployment of High Temperature Coating – Substrate Systems
This DMREF program engages a multidisciplinary team from Materials, Computer Science and Mechanical Engineering to develop a fundamental framework for design of a new class of multilayered systems that could impact new, energy efficient power generation and propulsion systems.
Tresa M. Pollock
The discovery of ternary and quaternary L12 intermetallic compounds in Co-Al-W-X systems provides a path for the development of a new class of high temperature structural materials1. This DMREF program engages a multidisciplinary team from Materials, Computer Science and Mechanical Engineering to develop a fundamental framework for design of a new class of multilayered systems that could impact new, energy efficient power generation and propulsion systems. Novel complementary computational, experimental and data tools are being developed and integrated with existing tools to explore composition space for exceptional properties.
During the past year of the program we have employed new tools based on density functional theory to:
•Demonstrate for the first time that vibrational entropy can stabilize the L12 phase at finite temperatures
•Permit quantitative assessment of the driving forces for segregation at superlattice intrinsic stacking faults2, shown in HAADF STEM and atom probe analyses (a,b)
•Search for new compositions with high SISF energies and corresponding good mechanical properties (c); new compositions synthesized as single crystals grown at UCSB via the Bridgman process demonstrate high stability (high solvus temperature) of the L12 phase, (d).