A combined phase field approach for martensitic transformations and damage

摘要

A combined continuum phase field model for martensitic transformations and fracture is introduced. The positive volume change that accompanies the phase transformation from austenite to martensite leads to an eigenstrain within the martensitic phase, which is considered within the present approach. Since the eigenstrain leads to both tensile and compressive loads, the model accounts for the sign of the local volume change. With aid of this model, the interactions between microcrack propagation and the formation of the martensitic phase are studied in two dimensions. Martensite forms in agreement with experimental observations at the crack tip and thus influences the crack formation. The numerical implementation is performed with finite elements. For the transient terms, an implicit time integration scheme is employed.