Low temperature ageing behaviour of quenched Cu-Al-Be shape memory alloy

Positron lifetime measurements are used to obtain the concentration of quenched-in Feint defects for different quenching temperatures and to determine their subsequent time evolution at room temperature, The corresponding: evolution of the transition temperature after the quench has also been measured by calorimetry. The fact that both quantities follow comparable time evolutions corroborates the claim that vacancies are responsible for the observed changes in the martensitic transition properties after quenching.