The study between the fracture behavior and the thermomechanical effect of aluminium alloy 2024-T3 by TPB cracked test

摘要

This study derives the relation between the fracture behavior and the thermo-mechanical effect of aluminum alloys 2024-T3 and 7075-T6 by means of three point bending (TPB) testing at various thicknesses and loading speeds. Observation and analysis of macro and micro fractostructure are made on specimens after testing. Temperature variation of the specimen surface along crack tip is measured and recorded during loading to fracture, thus studying the thermomechanical effect correlated to fracture behavior of the aeronautic aluminum alloys. Result shows that, in thinner specimens, fractostructure mainly consists of dimple and ductile tear ridge. The ductile tear ridge shows more clearly in thicker specimens. Thermomechanical effect results show that plastic deformation during loading to fracture is small. The results of TPB tests indicate that a maximum temperature drop appears at a loading speed of about 60 mm/min.