Experimental and predicted fatigue crack growth resistance in Al2124/Al2124+35%SiC(3 mu m) bimaterial

When a fatigue crack approaches perpendicularly to the macroscopically planar interface of an A12124/AI2124+35%SiC(3 mum) bimaterial. the fatigue crack growth resistance is affected by the elastic-plastic mismatch, thermal residual stresses and the direction of crack approach to the interface. The main purpose of this work is to compare experimental and predicted behaviour to evaluate how such parameters affect the fatigue crack growth resistance in an A12124/AI2124+35%SiC(3 mum) bimaterial. Results show that the effective stress ratio method (R') alone cannot predict the fatigue crack growth resistance of such bimaterials accurately and the effects of the elastic-plastic mismatch must therefore be taken into account. (C) 2003 Elsevier Science Ltd. All rights reserved.