Effect of frequency on MW assisted sintering: 2.45 GHz versus 5.8 GHz

Abstract

Innovative non-conventional approaches, such as microwave sintering, are being developed as a method for sintering a variety of materials which shown advantages over conventional sintering procedures. This work involves an investigation of the microwave sintering of an ATZ composite with two different microwave applicators and frequency generators: 2.45 GHz and 5.8 GHz. Zirconia doped with ceria and toughened with alumina (10Ce-TZP/Al₂O₃) is the composite used in this study. The samples were sintered by microwave in air at 1200 and 1300 °C with 10 min of dwell time at 2.45 and 5.8 GHz in order to evaluate their effects on sintering, using an optimized experimental configuration. In addition, the mechanical properties of MW-sintered samples were compared with those obtained for the same composites sintered by the conventional method (1500 °C/120 min), such as relative density, hardness and fracture toughness.

Keywords

Zirconia-alumina composites ceria microwave sintering low temperature degradation phase transformation

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