Crack initiation and growth in an Zn-Cu-Al PE alloy

Cu-Zn-Al shape memory alloys exhibit shape memory behavior within a certain range of composition. They are characterized by a stable high temperature disordered bcc structure named β-phase, followed by a transition to a B2 structure after appropriate cooling and from secondary B2 to DO3 ordering under other cooling procedures. It is also know that martensite stabilization can be reduced by a step-quenched treatment. Shape memory properties are often absolutely interesting and many grades of shape memory alloys are extensively used in the technological world, e. g. in surgery and dentistry. Copper-based shape memory alloys are preferred for their good memory properties and low cost of production. In this work, the main crack initiation and its propagation in an tensile test is analyzed in order to evaluate crack path and its behavior corresponding to low and to high deformation values. Furthermore, results are associated to X-Ray diffraction in order to correlate structural transition involved in an Cu-Zn-Al alloy characterized by a PE behavior.