Influence of microstructural size on the thermal shock behavior of Al2O3-Er3Al5O12 directionally solidified eutectics

Abstract

We analyze the thermal shock resistance of directionally solidified eutectics. When quenching in water, the resistance starts to deteriorate with temperature differences in the range 260 to 300 K, almost independent of the microstructure size (or initial flexural strength). Unlike other strong, dense ceramics, the loss of strength is gradual upon quenching in boiling water. The onset of crack propagation seems to be controlled by the mismatch of the thermal and elastic properties of the component phases, while the length of the propagated cracks is limited by their quantity, which is estimated to scale approximately with the interface density.

Mechanical performance and thermal shock resistance of alumina composites fabricated by temperature gradient spark plasma sintering

“…Thermal shock resistance (TSR) is one of a major topic for the application of alumina composites in the high-temperature environment. The TSR has been investigated by various researchers for better understanding the mechanisms of improving TSR of Al 2 O 3 composites [31][32][33][34][35]. The improved TSR of Al 2 O 3 -SiC w composites were achieved by enhancing its densi cation and the content of yttrium aluminum garner, producing of tabular alumina [31].…”

“…The TSR of laminated Al 2 O 3 /Mo-Al 2 O 3 composites was improved by introducing heat-resistant particles into weak layers and improving the interfacial bonding strength of the two layers [32]. [34]. There are many factors in uencing the TSR of ceramic composite, including mechanical properties and thermal physical parameters, thermal expansion coe cient, etc.…”