Processing and Mechanical Properties of RuAl-Based Alloys

Alloys of Ru-Al-Cr with compositions between Ru-10Al-35Cr and Ru-3Al-39Cr (at.%) were directionally solidified and heat treated to produce single phase hcp-Ru(Cr,Al) and two phase B2-hcp microstructures. The room temperature fracture toughness, tensile behavior, and cyclic oxidation behavior at 1100°C were investigated and compared to previous results measured from RuAl and Ru-Al-Mo alloys. For microstructures consisting of a Ru(Cr,Al) matrix with fine RuAl precipitate, a good room temperature fracture toughness, tensile ductility, and oxidation resistance at 1100°C were measured.