Titanium and its alloys represent an important family of materials providing energy efficiency along with mechanical and environmental advantages but have seen only limited application primarily due to the high cost of production. Electric field-assisted sintering technology, sometimes called spark plasma sintering, is a novel process for the consolidation of powders or particulates that offers cost advantages over conventional approaches. The team of this Grant Opportunity for Academic Liaison with Industry (GOALI) project will contribute to the fundamental understanding of molecular diffusion behavior during field-assisted sintering for titanium and titanium powders that will enable cost-effective manufacturing of these materials while maintaining material attributes such as high strength, low density and environmental inertness. The findings will impact both the automotive and aerospace industries. The collaborative university-industry research team will educate university students as well as provide outreach activities to attract high school students to engineering careers.
Availability of diffusion data in multicomponent systems has been scarce due to the complexity of diffusion analyses and the dependence of interdiffusion coefficients on composition. This has prevented accurate modeling of the kinetics of sintering for ternary or higher order systems encountered in commercially important materials. The research team will generate ternary interdiffusion coefficients for titanium-aluminum-niobium systems, an important material system for automotive and aerospace applications. In the presence of an electric field during field-assisted sintering, the phase equilibrium can be altered giving rise to new phases or eliminating certain phases during processing. The effects of an imposed electric field and microstructural length scale will be assessed through a set of experiments and simulations that will provide insight into the thermodynamics and kinetics of the interdiffusion and phase equilibria/transformation for the chosen material system. With this insight, titanium alloys can be designed and manufactured with desired properties at lower cost than is available today.
