| Fracture behavior of NiAl 50-50 single crystal was studied in compact tension and double-cantilever beam specimens. The results of the tests established The level of fracture toughness showed strong dependence on the heat treatment the material had received in the 200Since such sensitivity to low temperature heat treatments is often indicative of a strain aging phenomenon, the Portevin-le Chatelier effect was shown to take place in NiAl in compression tests, where serrated yielding was observed over approximately 180It was also attempted to increase mobile dislocation density by means of prestraining, but the results of these experiments were confused by the influence of strain aging. However, the general trend in the fracture toughness data suggests that inherent ductility in NiAl is much higher than previously thought and is probably dependent on the mobile dislocation density. |
