The effect of ageing on physical properties of Cu-Al-Mn shape memory alloys

In this study, Cu-%23,01 Al-%4,34Mn (%at.), Cu-%26,56Al-%3,06Mn (%at.) and Cu-%27,96Al-%4,60Mn (%at.) shape memory alloys were fabricated by melting method and the effect of ageing process on physical properties Cu-Al-Mn ternary shape memory alloys were investigated. In the aim of this work, each alloy was aged at 200, 300, 400 and 500 °C for 1 hour and then quenched in water at room temperature. After this process, the un-aged and aged samples were thermally investigated by Differential Scanning Calorimetry (DSC) to determine the characteristic transformation temperatures, enthalpy, entropy, values. It was observed that the characteristic transformation temperatures were increased in aged samples. The increase of the characteristic transformation temperatures is due to the precipitate phase and the for mation of the precipitate phase was changed according to ageing temperature and also the martensit variants were disappeared with the increase of precipitate phase and this result was supported with the metallographic observations. The lattice parameters crystal structures and diffraction patterns of the alloys were calculated by X-Ray analysis at room temperature.