Novel two-step processing route combining mechanical alloying and microwave hybrid sintering to fabricate dense La9.33Si2Ge4O26 for SOFCs

Abstract In this work, microwave hybrid sintering at 1300 and 1350 °C was carried out for densification of La 9.33 Si 2 Ge 4 O 26 mechanically alloyed powder with apatite structure. The pellets sintered at these two temperatures present the same structure (apatite) with relative densities of 92 and 96%, respectively. Mechanical analysis performed on sintered materials revealed the following results: hardness of 7.1 and 8.0 GPa, Young's modulus of 122 and 133 GPa, yield strength of 1807 and 2073 MPa and fracture toughness of 1.5 and 1.0 MPa m 1/2 , respectively.