Journal de physique iv vol:1 issue:C4 pages:189-197
The stability and lifetime of a shape memory device is characterised by the changes of its transformation temperatures. its cold shape, its hot shape, its global two way shape memory effect, its recovery stress. This global behaviour is influenced by a complex combination of internal and external parameters. Internal parameters are: the alloy system, the alloy composition, the type of transformation and the lattice structure including defects. External parameters are : the thermomechanical treatments, the way of training, the applied stress, the imposed shape memory strain, the amplitude of temperature cycling, the absolute temperature of the environment.