Air Force (AF) weapons continuously demand higher weapon performance, so efforts are needed to optimize material performance, manufacturability (capacity and surge), and cost. Furthermore, the extreme environments of weapon applications (pressure, temperature, strain, strain rate, and fracture) limit existing data, including constitutive material models for computational design tools, in these regimes. The goal of this work, therefore, is to characterize exiting materials and structures and/or develop new metals and manufacturing methods for improved performance in AF applications. Novel manufacturing methods and material chemistries must be characterized with respect to chemistry-processing-(micro)structure-properties-performance (CPSPP) in extreme loading conditions and used to develop constitutive material models for improved ordnance design tools, all the while incorporating material cost and manufacturability design constraints.

The primary technical challenges of this work consider (1) the influence of novel manufacturing methods (e.g. investment casting and additive manufacturing) and materials on rate-, pressure-, and direction-dependent (i.e. anisotropy) mechanical properties are not well understood and (2) computational design tools (e.g. CALPHAD, finite element analysis) are not yet robust enough to provide predictive capabilities. Therefore, CPSPP relationships are to be characterized via mechanical property testing and evaluation to systematically understand the influence of chemistry and thermo-mechanical processing on rate-dependent material properties and component level performance. Microscopic inspection will evaluate microstructure and mesostructured control for location specific properties.

Manufacturing and material processing capabilities relevant to this program include polymer and metal additive manufacturing (AM) systems, metal alloy casting, and thermal processing chambers for heat treatment. Mechanical characterization capabilities to facilitate this work include low-rate servo-hydraulic and electromechanical load frames and high-rate split-Hopkinson pressure bar systems. These are complemented with chemical/compositional analysis equipment, high resolution optical microscopes, scanning electron microscopes with electron backscattered diffraction (EBSD) and energy dispersive spectroscopy (EDS) sensors, full-field shape and deformation analysis tools (e.g., 3D scanning and digital image correlation), and time-resolved interferometry systems (e.g. VISAR and PDV). Materials of interest include – but are not limited to – metal alloys, structural reactive materials, bioinspired materials, fiber reinforced composites, functionally-graded composites, and additively manufactured materials and structures.

Applicants must be US citizens.

Mechanical properties; Metals; Metallurgy; Microstructure; High Strain Rate; Advanced Manufacturing; Experimental Mechanics; Constitutive Material Models

citizenship

Open to U.S. citizens

level

Open to Postdoctoral and Senior applicants

Additional Benefits

relocation

Awardees who reside more than 50 miles from their host laboratory and remain on tenure for at least six months are eligible for paid relocation to within the vicinity of their host laboratory.

health insurance

A group health insurance program is available to awardees and their qualifying dependents in the United States.