Improvements of fatigue behaviour in 2014 Al alloy by solution heat treating and age-hardening

In order to understand the fundamental fatigue behaviour of 2014 Al alloy, rotating bending Fatigue tests have been carried out using materials with an as-received and four different microstructure feature produced by solution heat treating at 410, 450, 480 and 510 degreesC for 2 h. then quenching in cold water (at 15 degreesC), followed by aging at 190 degreesC for 7 h. Scanning electron microscopy and X-ray diffraction were carried out to characterize the structure properties resulting from different. heat treatments. The fatigue test results showed that the solution temperature have very Strong influence on fatigue strength. The fatigue strength at 10(7) cycles of Al alloy made by aging after solution treating temperature of 510 degreesC was improved by approximately 43%, compared with as cast alloy. In addition. the fractured fatigue specimens were examined using a scanning electron microscopy in order to clarify fracture initiation points. (C) 2003 Elsevier Ltd. All rights reserved.