Fabrication and Characteristics of 8YSZ/Ni Functionally Graded Materials byApplying Spark Plasma Sintering Procedure

Functionally graded materials (FGM) in the form of layered structure consisting of yttria stabilizedzirconia (8 % mol Y2O3) and nickel were fabricated by spark plasma sintering procedure. The relativedensity, linear shrinkage and Vickers hardness of each layer of graded materials were measured. Themicrostructure and the composition of these components were studied. The results obtained show thatfunctionally graded materials produced by spark plasma sintering exhibited consequently fully densespecimens. Also, the results demonstrate that the composition and microstructure of YSZ/Ni FGMhave the expected gradient distribution. There are no macroscopic distinct interfaces in YSZ/Ni FGMdue to the gradient change in components. This good continuity of microstructure can eliminate thedisadvantage of traditional macroscopic interface in YSZ/Ni joint, and reflect the design idea of FGM.Vicker’s hardness of YSZ/Ni is lower than that of pure zirconia (YSZ) and increases by increasing therelative density of the layer of YSZ/Ni.