Mechanical Performance of ZrO2-Ni Functionally Graded Material by Powder Metallurgy

The mechanical performance of a ZrO2-Ni functionally graded material (FGM) developed by powder metallurgy was investigated by means of three-point bending test. It was shown that the mechanical behavior of ZrO2-Ni system strongly depends on constitutional variation, exhibiting typical behavior of elasto-plastic deformation similar to metallic material in the Ni-rich composition and typical behavior of elastic deformation and macroscopic brittle fracture in the ZrO2-rich composition. The mechanical properties of ZrO2-Ni system also display various gradient distributions corresponding to constitutional change. With the rise of Ni content, Vickers hardness decreases, but fracture toughness increases remarkably. Young’s modulus changes corresponding to the distribution of porosity. Bending strength is quite sensitive to microstructural factors, and its peak and valley point are relevant to the dispersion strengthening of ZrO2 particles and the distributional transition of components, respectively.