Residual stresses in Al2O3–ZrO2 (3 mol.% Y2O3) directionally solidified eutectic ceramics as a function of temperature

Directionally solidified eutectics are in situ composites grown from the melt. Due to the differences in the thermoelastic properties of the different phases present in the material, these composites often exhibit residual stresses that can affect their mechanical properties. In this work we use neutron diffraction to investigate residual stresses in Al2O3–ZrO2 eutectic composites as a function of temperature, for samples processed at two different growth rates, 10 mm/h and 750 mm/h. Our results show that the stress-free temperature is in the range of 1200 ± 200 °C. We explain the experimental observations based on the thermoelastic properties of the phases in the material and confirm our measurements using a simple, self-consistent model.

► Studied residual stresses in melt-processed eutectic ceramic composites. ► Using neutron diffraction to determine them as a function of temperature. ► Measured their stress free temperature directly instead of extrapolating RT data. ► Studied the effect of eutectic processing conditions on the residual stresses. ► Explained the results using a simple thermoelastic model.