Low cycle fatigue properties of AA2519-Ti6Al4V laminate bonded by explosion welding

The paper presents the effect of heat treatment on low cycle fatigue properties and the course of fatigue cracking in AA2519/Ti6Al4V sandwich laminates. The laminate is made by explosion welding, using an intermediate layer in the form of an alloy AA1050. The strength properties of bonds were determined during fatigue tests conducted in conditions of constant total strain amplitude εac. This paper describes the impact on the test conditions on the shape of the hysteresis loop, the course of the cyclical strengthening/weakening of the material and the fatigue strength. Test results were extended to the analysis of the surface of the resulting fatigue fractures. The characteristic traits of fatigue cracking were investigated by examining the microstructure of the fracture surface using the scanning electron microscope.