Crack path in a Zn-Cu-Al PE alloy under uniaxial load

Pseudo-elastic (PE) materials are an important class of metallic alloy which exhibit unique features with respect to common engineering metals. Because of these unique properties, PEs are able to recover their original shape after high values of mechanical deformations, by removing the mechanical load (PE). From the microstructural point of view shape memory and pseudo-elastic effects are due to a reversible solid state microstructural diffusionless transitions from austenite to martensite, which can be activated by mechanical and/or thermal loads. Copper-based shape memory alloys are preferred for their good memory properties and low cost of production. This paper describes the main crack initiation and its propagation in an tensile test in order to evaluate crack path and its behaviour at low and at high values of deformation. Both grain boundary chemical properties and X-ray diffraction will be discussed in order to correlate structural transition involved in an Cu-Zn-Al alloy characterized by a PE behaviour.