MODELLING OF INTERACTION BETWEEN PLASTICITY AND MARTENSITIC PHASE TRANSFORMATION IN SHAPE MEMORY ALLOYS

Abstract

DISLOCATION SLIP AND MARTENSITIC PHASE TRANSFORMATION ARE TWO IMPORTANT DEFORMATION MECHANISMS IN SHAPE MEMORY ALLOYS (SMAS) AND THE INTERACTION BETWEEN THEM AFFECTS THE PSEUDOELASTICITY AND SHAPE MEMORY EFFECT BEHAVIORS. THESE INFLUENCE THE REVERSIBILITY BEHAVIOR AND ALSO ACTUATION BEHAVIOR OF SMAS UNDER CYCLIC LOADINGS. TO REDUCE IRREVERSIBILITY AND IMPROVE ACTUATION BEHAVIOR, A LOT OF STUDIES HAVE BEEN CONDUCTED IN THE RECENT YEARS. THE AIM OF THIS STUDY IS TO MODEL THE DISLOCATION SLIP AND PHASE TRANSFORMATION MECHANISMS IN MICRO-SCALE AND INVESTIGATE THE MICRO-STRUCTURAL EFFECTS OF (I) DISLOCATIONS ON MARTENSITIC TRANSFORMATION, (II) PHASE TRANSFORMATION ON DISLOCATION SLIP AND (III) INTERACTION OF BOTH PHENOMENON ON THE TOTAL REVERSIBILITY OF SMA.