Tuning of phase content, microstructure and thermal expansion of MgPSZ

Abstract

MgO partially stabilized zirconia (xMgPSZ, with x = 3–14 mol% MgO) was prepared by a ceramic route, starting from pure metal oxides. 7.5MgPSZ, the focus of this work, was sintered at 1700 °C and cooled at various rates (1, 2 or 4 °C/min), without or with 1 or 2 intermediate dwells (1400, 1300, and 1000 °C), and dwell durations (1–6 h). Customized thermal expansion (TE) data analysis is used to estimate the monoclinic (M) phase content (with discrimination between large and small particles), while powder X-ray diffraction (XRD) provides an accurate cubic (C) phase assessment. With the tetragonal (T) phase content determined from balance to 100%, detailed sets of structural (M, C, T) and microstructural information (M particle size), are grouped in novel radar-type charts. Original benchmarking exercises using literature data on up thermal shock resistance and the characteristics of a commercial MgPSZ, provide unique insights on the thermal performance of these materials, and property tuning rationale.