Crystallographic and strain mapping in zirconia-based ceramics: an in situ 3D reconstruction during heating of mono- and polycristalline mic

Ceramic materials present an elastic-brittle behaviour at room temperature, leading to fracture before any sign of plasticity. This is linked to the low mobility of dislocations, compromising any ductility as is the case of metallic materials. Some zirconia-based ceramics can exhibit real plasticity at room temperature thanks to a martensitic phase transformation mechanism (tetragonal to monoclinic), similar to the transformation induced plasticity in shape-memory alloys. With a stress and/or temperature-controlled phase transformation as a source of toughening, zirconia doped with cerium oxide ceramics are particularly remarkable, with a plastic deformation on the order of one percent before rupture and lower sensitivity to the presence of defects. To fully describe this behavior, we conduct an in situ heating experiment with 3DXRD and DCT analyses, mapping out the strain tensors, as well as crystallographic orientations during the reverse phase transformation.