High Strength Stress Corrosion Resistant Aluminum Casting Alloys

The United States Marine Corps (USMC) is pursuing high-performance aluminum castings for structural components of the Expeditionary Fighting Vehicle (EFV). Aluminum alloy A206 has been considered for these applications; however, this alloy is susceptible to hot tearing during casting, and has inferior stress-corrosion cracking (SCC) resistance. Under this proposed SBIR program, QuesTek Innovations LLC, a leader in the field of computational materials design, will design and develop a new high-strength SCC-resistant castable aluminum alloy for the waterjet inlet housing and/or steering bucket applications. The Materials by Design framework will use QuesTek"s state-of-the-art computational design tools for aluminum alloys, including custom thermodynamic and kinetic databases, microstructural evolution models, physics-based strength models, solidification and inoculation process simulations, and stress-corrosion cracking models. Our Phase I collaborators, Material Strategies, Inc. and Eck Industries, Inc. will assist QuesTek in Phase I alloy fabrication, castability testing and will provide process-related design expertise. In the program QuesTek will also partner with OEMs who will help define the material and process requirement matrix, and ultimately lead the alloy implementation. Concept feasibility will be demonstrated on model alloys fabricated in the Phase I program. Production-scale fabrication of the designed alloy will be demonstrated in Phase II.