THE THERMAL STABILITY OF THE MICROSTRUCTURE OF γ-BASED TITANIUM ALUMINIDES

摘要

The thermal stability of the microstructure of γ-based titanium aluminides after aging at elevated temperatures was studied by transmission and analytical electron microscopy (TEM and AEM, respectively) as well as by optical microscopy. Predominantly lamellar microstructures of Ti-47Al (at./100), Ti-47Al + B (140appm) and Ti-47Al + B + W (0.5at./100) alloys were produced by heat-treatment at 1400℃ for 1h followed by furnace cooling. The average lamellar spacing of the as-heat treated was measurably finer in both alloys with solute additions (400nm in Ti-47Al, 170-190nm in alloys modified with B or W + B).