Effect of hydrogen on microstructure and high temperature deformation of (TiB + TiC)/Ti–6Al–4V composite

Abstract

(TiB + TiC)/Ti–6Al–4V composite and Ti–6Al–4V alloy were hydrogenated. The phases were identified by X-ray diffraction (XRD). Microstructures of hydrogenated titanium matrix composite (TMC) and Ti–6Al–4V alloy were examined by optical microscopy (OM). Dependence of transformation temperatures on hydrogen concentration was determined by metallography. The transformation temperatures decrease with hydrogen and reach a minimum at hydrogen concentrations of 0.40 wt.% and greater. High temperature tensile tests were performed. The results indicate the elongation is improved at low and high hydrogen concentration but little at medium hydrogen concentration. The stress decreases at low hydrogen concentration, reaches a minimum at medium hydrogen concentration and then increases at high hydrogen concentration. Proper hydrogen concentration favors high temperature deformation of TMC.