Multiscale creep characterization and modeling of a zirconia-rich fused-cast refractory
Résumé
This work aims at investigating the mechanical behaviour of a zirconia-rich fused-cast refractory at high temperature ( C). The geometry of the zirconia phase was analysed on samples having contents of amorphous phase ranging from 12 to 24% in volume, from 3D images obtained using the X-ray computed micro-tomography technique. The sharp intrication of the dendrites creates a continous zirconia skeleton which was characterized experimentally. Results at high temperature show that deformation is controlled by zirconia, whereas the amorphous phase does not play any structural role. Finite-element simulations have been carried out to predict the creep behaviour of the aggregate. The creep law of the zirconia skeleton was identified by an inverse method from a creep test at C and from the 3D real morphology of the dendritic zirconia structure. Simulation results confirm that the rheology of the aggregate is controlled by the zirconia skeleton and a good agreement was observed between numerical creep tests and experiments.