Fabrication of ZrO2/AISI316L functionally graded materials for joint prostheses

In this study, ZrO2/AISI316L functionally graded materials (FGMs) were fabricated for use in joint prostheses and their mechanical and biotribological properties were evaluated through fracture toughness, bending strength, and wear resistance studies. To exploit ceramic/metal composites for joint prostheses, efficient fabrication of FGMs with stable mechanical and tribological properties is desirable. The material was designed to eliminate the defects of low fracture toughness in the case of ceramics and of degradation and toxicity in the case of metals when used in artificial joints. Spark plasma sintering was used to consolidate powders prepared by mixing ZrO2 (3Y-PSZ) with 10-50 vol.% of AISI316L granules. The mechanical and tribological properties of the fabricated ZrO2/AISI316L FGMs depended on the thickness of the layers from which they were composed. The fabricated FGMs showed a higher fracture toughness than a monolithic ZrO2 when the thickness of the layers was greater than 2.0 mm. The wear resistance and bending strength response were evaluated as a function of the structure of the FGMs.