Autor(es): Antunes, Luiz Henrique Martinez ; Quintero, John Jairo Hoyos ; Andrade, Tathiane Caminha ; Sarvezuk, Paulo Willian Carvalho ; Wu, Leonardo ; Ávila, J.A. ; Oliveira, J.P. ; Schell, N. ; Jardini, André Luiz ; Žilková, J. ; Farina, Paula Fernanda da Silva ; Abreu, Hamilton Ferreira Gomes de ; Béreš, Miloslav
Data: 2022
Origem: Oasisbr
Assunto(s): CoCrMo alloy; Martensitic phase transformation; In-situ synchrotron X-ray diffraction; Peak broadening; Variant selection
The wear resistance of the biomedical low-carbon Co-28Cr-6Mo (wt.-%) alloy is primarily determined by the onset and magnitude of the face-centered cubic to hexagonal close-packed deformation-induced martensitic phase transformation. In metal-on-metal joint bearings, local plastic deformation occurs on the surface and in the subsurface regions. This can cause deformation-assisted structural changes in the material, such as mechanical twinning and/or martensitic transformation. In the present work, we report the structural transition on the surface and bulk of a laser powder bed fusion additively manufactured Co-28Cr-6Mo alloy in response to an externally imposed load. This study was possible using in-situ synchrotron X-ray diffraction at two different energy levels. Our results revealed that from tensile deformation to fracture, the phase transformation kinetics and magnitude were marginally higher on the surface. During transformation, {200}FCC peak broadening was observed in the bulk and this was attributed to stacking fault accumulation.
