Prediction of the variation of elastic modulus in ZrO2/NiCr functionally graded materials

The variation of elastic modulus in the ZrO2/NiCr functionally graded materials (FGMs) is investigated experimentally and theoretically. To obtain the variation of the elastic modulus in the FGMs experimentally, 3-point bending tests are conducted on the homogeneous specimens with different volume fractions of NiCr. The experimental results show that the elastic moduli decrease obviously with the increase of NiCr, which differ greatly from those predicted by the traditional Mori–Tanaka method. From the fractographs of the homogeneous specimens, it is found that the particles/matrix interfaces are bonded weakly and easy to debond. Based on the microstructure and fracture mechanism of the FGMs and homogeneous specimens, the modified Mori–Tanaka method from Tan is applied to predict the elastic modulus. The debonding process of the particles/matrix interface is characterized by a cohesive law. The predicted results agree well with the experimental ones.