Properties of eutectic Ru–Al alloy produced by ingot metallurgy

This work presents microstructural, chemical and mechanical characterization of two alloys (Ru70Al30 and Ru75Al25 (at.%)), which lie close to eutectic point in Ru–Al system. According to the microstructure and chemical analysis, eutectic composition of Ru76Al24 (at.%) has been proposed. RuAl lamellae showed intrinsic deformability when compared with α-Ru lamellae. However, due to high interface density (λ=0.6 μm) of fine eutectic structure a joint action of individual phases produces the effect which results in good overall mechanical properties (R0.2=883 MPa, Rmax=3178 MPa and Af=23%). The fracture appearance of both lamellar and rod-like eutectics is fine and fibrous in nature, which is consistent with good ductility and toughness. RuAl dendrites failed in transgranular manner or interface decohesion occurred between RuAl dendrites and Ru halos.