Structural and mechanical properties of Ti–Al–Nb–Mo–B alloy produced from the SHS powder subjected to high-energy ball milling

Abstract

Abstract Ti-Al-Nb-Mo-B alloy was successfully produced via high-energy ball milling (HEBM), self-propagating high-temperature synthesis (SHS) and hot isostatic pressing (HIP) techniques. HEBM was used to prepare powder mixtures with different types of microstructure and homogeneous distribution of the components. After SHS in thermal explosion mode powder grains with a microgradient structure were synthesized: their central part consists of α2-Ti3Al and the peripheral part consists of γ-TiAl. Compacted samples with duplex fine-grained structure and high thermomechanical properties (σ0.2 = 1245 MPa and 524 at 20°C and 800°C, respectively) have been obtained using the HIP technology. It was found, that mechanical twinning is the preferential deformation mechanism of the studied Ti-Al-Nb-Mo-B alloy.