A new graded-porosity ZrO2(3Y)/Ni composites can be fabricated by cold isostatic pressing and pressureless sintering process.ZrO2(3Y) ceramic with large connecting open pores and permeability were used as porous layer.Microscopic observations revealed that the microstructure of the mullite/Mo FGM had a gradual stepwise variation.The mechanical properties of the ZrO2(3Y)/Ni composites system had graded distributions that depend on the composition variation across the thickness.The FGM specimens had better mechanical properties than did monolithic mullite.The mechanical properties of FGMs were influenced by the sintering-induced residual thermal stress.The mechanism of crack formation in the FGMs was discussed.