Microstructure and mechanical properties of a β Nb–Ti based alloy

Abstract

This paper presents the results of a study of microstructure and mechanical properties (tensile and creep behavior) of a multicomponent body-centered-cubic Nb–35Ti–6Al–5Cr–8V–1W–0.5Mo–0.3Hf–0.5C alloy (compositions quoted in atomic% unless stated otherwise). The double extruded material is shown to have a Van Gogh Sky microstructure that is formed as a result of the combined effects of microsegregation and deformation gradients. The effects of recrystallization heat treatments on microstructure were examined in an effort to produce a fully recrystallized microstructure. The changes in tensile properties and fracture mechanisms at different temperatures (27–704 °C) are discussed for material in fully recrystallized condition. The micromechanisms of creep deformation at 704 °C are also elucidated for the fully recrystallized condition.