The damage process in a biomedical Co–29Cr–6Mo–0.14N alloy analyzed by X-ray tomography and electron backscattered diffraction

The damage process leading to fracture during tensile testing of a biomedical grade Co–29Cr–6Mo–0.14N alloy was analyzed on the basis of three-dimensional damage observation using X-ray tomography and electron backscattered diffraction of the fractured specimen. Initial cracking occurred at grain and annealing twin boundaries, where strain concentrates due to impingement of ε-hcp plates formed through strain-induced martensitic transformation (SIMT). Cracks propagated along the interface between the γ-fcc matrix and SIMTed ε-hcp on {1 1 1}, resulting in the occurrence of a quasi-cleavage fracture.