Fabrication and mechanical property of Y-TZP/Al₂O₃/Mo nanocomposites

Ceramic nanocomposites are the most promising materials for industrial nano-ceramic material at present, and have become an international research focus. The addition of a metal second phase may improve the tribological and mechanical properties of ceramic nanocomposites. Yttria-stabilized tetragonal zirconia polycrystals (Y-TZP)/Al₂O₃/Mo nanocomposites were prepared by hot-pressing using nano-sized ZrO₂-Y₂O₃- Al₂O₃ as the matrix and metal molybdenum with micro-size as a dopant. The effects of Mo content on the microstructure and mechanical property of Y-TZP/Al₂O₃/Mo ceramic-metal nanocomposites were studied. The results show that the Y-TZP/Al₂O₃/Mo mixed structures are composed of intra-type, inter-type, and nano/nano type, which make the material have very high fracture toughness. A highest indentation toughness of 20.8 MPa·m^1/2 can be achieved for the Y-TZP/Al₂O₃/Mo nanocomposite with an Mo mass fraction of 60%.