Abstract
This paper described the thermodynamic analysis and experimental verification of interface reactions between iron aluminide intermetallic and tetragonal zirconia. Thermodynamic analysis confirmed that chemical reactions between Fe–Al intermetallic and ZrO2 (3 mol.–%Y2O3 stabilised zirconia) mainly depended on the Al content in Fe–Al intermetallic. For ZrO2(3Y)/Fe3Al composite, the interface reactions to form Al2O3 and ZrAl2 would take place when Al content was >40 at-% in Fe–Al intermetallic, while no interface reaction occurred when using Fe3Al as toughening phase. ZrO2(3Y)/Fe3Al composite was synthesised by hot press sintering to further verify the thermodynamic analysis of interface reactions between iron aluminide intermetallic and tetragonal zirconia. The phase composition, morphology and interface structure of ZrO2(3Y)/Fe3Al were investigated by X-ray diffraction, SEM and TEM. The results show that Fe3Al was thermodynamic stable in ZrO2(3Y) matrix, which was in good agreement with thermodynamically analysis.
Acknowledgements
This work is supported by the National Natural Science Foundation of China (grant no. 51172095) and the National Natural Science Foundation of China (grant no. 61102006).