Phase field modelling of fracture and fatigue in Shape Memory Alloys

We present a new phase field framework for modelling fracture and fatigue in Shape Memory Alloys (SMAs). The constitutive model captures the superelastic behaviour of SMAs damage is driven by elastic transformation strain energy densities. consider both assumption constant case dependent on martensitic volume fraction. implemented an implicit time integration scheme, with monolithic staggered solution strategies. potential this formulation showcased number paradigmatic problems. First, boundary layer used to examine crack tip fields compute growth resistance curves (R-curves). show that able capture main features associated SMAs, including toughening effect stress-induced transformation. Insight gained into role temperature, material strength, density function homogenisation. Secondly, several 2D 3D value problems are addressed, demonstrating capabilities capturing complex cracking phenomena such as unstable growth, mixed-mode or interaction between cracks. Finally, extended nucleation propagation biomedical stents, application nitinol SMAs.