Titanium Alloys Production by Powder Metallurgy for Automotive Applications

The use of alternative materials in automotive production can lead to both significant weight reductions and oftentimes functional improvements as well. Titanium and its alloys have unique properties that enable its use in the aerospace industry like its high strength-to-weight ratio, good resistance to many corrosive environments, and can be used over a wide range of temperatures. Despite these high expectations and the numerous advantages of titanium materials, their use has always failed just for a single reason: price. Powder metallurgy (P/M) of titanium and Ti-based alloys may lead to the obtainment of components having weak-to-absent textures, uniform grain structure and higher homogeneity at lower costs (a necessary prerequisite to expand the use of titanium and its alloys) compared with conventional wrought products. In this work Ti-6Al-4V and Ti-48Al-2Cr-2Nb (γTi-Al) were produced by P/M in order to expand the application in automotive area. Samples were produced by mixing of initial metallic powders followed by uniaxial and cold isostatic pressing with subsequent densification by sintering between 900-1400 °C, in vacuum. Sintered samples were characterized for phase composition, microstructure, microhardness and mechanical properties by X-ray diffraction, scanning electron microscopy, Vickers indentation and tensile tests respectively. Density was measured by Archimedes method. It was shown that the samples were sintered to high densities with excellent mechanical properties and presented homogeneous microstructure with complete dissolution of alloying elements in the titanium matrix.