A MODEL FOR THERMAL FATIGUE IN AN ALUMINUM CASTING ALLOY

A model for simulating the constrained thermal fatigue of an aluminium casting alloy is presented in this work. The specimen being tested ha s its ends fixed to a given length while its centre is subjected to th ermal cycling. The thermal gradients developed within the test are cal culated by an explicit finite difference technique, and with them, the strain and stress gradients are calculated. The agreement between the predicted and measured values of stress is good enough to consider th at the model reflects the behaviour of the material. It is found that the predicted life of the specimen is higher than that experimentally observed, an effect that might be due to overageing of the material as the specimen is being tested.