Tribological analysis of alumina nanocomposites for orthopedics applications

In this study the tribological analysis of Al ₂O ₃ nanocomposites/Al ₂O ₃ pair; proposed as a candidate material to fabricate hip prostheses was carried out. Nanopowders of Al ₂O ₃ (AKP 50, 300 nm), TiO ₂ (PS-25, 50 nm) and Co metallic powder (Nilaco, 28 nm) were mixed and hot pressed. Wear test was carried out in a pin-on-plate tribometer, with a frequency of 1 Hz, a load of 49 N, for 4h; the counterface used was Al ₂O ₃. Mechanical properties as Vickers hardness, fracture toughness and Young's modulus were estimated using the indentation method. Distilled water and fetal bovine serum solution (FBSS) were used as environment. It was found that the specific wear rate of Al ₂O ₃ nanocomposites was about 10 ^-8 mm ³/N*m and the coefficients of friction were around 0.3-0.5 for FBSS. Worn surfaces were observed using SEM.