High temperature compressive properties and room temperature fracture toughness of directionally solidified NiAl-based eutectic alloy

A eutectic alloy NiAl–28Cr–5.94Mo–0.05Hf–0.01Ho (at.%) was directionally solidified by liquid metal cooling technique at two growth rates (3 and 10 mm/min). The aligned microstructure was finer and more disturbed at growth rate of 10 mm/min than that at 3 mm/min, while the compressive properties at 1373 K was independent of the growth rate for these two alloys. The yield strength at 1373 K of the alloys produced by liquid metal cooling technique was 26% higher than that by the conventional Bridgeman technique. The fracture toughness of the alloy at 10 mm/min is a little lower than that at 3 mm/min, but about 47% higher than that of the alloy produced by Bridgeman technique.