Photo of Peter Walker

Peter Walker

Ph.D Student

Degrees:Ph.D (Present)

My work focuses on the additive manufacturing of Ti-6Al-4V and lattice materials. Lattice materials have always been of great interest in many fields of engineering for their potentially weight savings, though this interest has long been limited to theory due to the challenges in manufacturing. Conventional manufacturing methods have long kept the production of lattice materials prohibitively expensive, and certain lattice topologies have proven impossible to manufacture by conventional methods (e.g. casting or milling. Additive manufacturing allows for the production of lattice materials, as well as tailoring of certain microstructural elements, especially for complex alloys such as Ti-6Al-4V. By optimizing at the microstructural level and at the lattice material’s microscopic level, our hope is to produce a material with a better strength to weight ratio than would be achieved by  either optimization process alone.

Currently I’m researching the effects of the various build parameters (build direction, scan strategy, etc) have on the microstructural properties (for example the texturing of the beta grains in the alpha matrix, prevalence of certain microstructural defects, etc) through various experimental methodologies, such as tensile testing, electron and optical microscopy and X-ray diffraction. The goal is to compile a quantitative model relating these build inputs to the modulus, yield stress and fracture toughness of the material. This will be fed into the Finite Element Modeling and  optimization of the cellular material in NASTRAN. Initially the focus will be on the static loading case but I hope to expand my research into the fatigue life optimization of cellular materials.