Short-term tribological study of ceramic biomaterials against MgAZ31 under bio-lubricants for hip joint replacements

The ceramic materials prove to be better alternative to metallic and polyethylene implants. The AZ31 alloy exhibits better biocompatible properties compared with existing metallic implants. The present study investigated the friction and wear rate properties of silicon nitride (Si3N4), Alumina (Al2O3), zirconia (ZrO2) and zirconia toughened alumina (ZTA) against AZ31 for 2 km under bio-lubricants using ball-on-disc (B-o-D) tribometer. The bio-lubricants considered for the current study include Ringer's solution, distilled water, saline solution and phosphate buffer saline (PBS). The B-o-D load of 20 N which equals the gait load of normal walking is taken into consideration for current study. Amongst the ceramic materials considered, ZTA and Si3N4 ceramic biomaterials showed better tribological behaviour for PBS bio-lubricant and comparatively maximum wear rate was observed for alumina-AZ31 combination for all bio-lubricants. Amongst the bio-lubricants, distilled water and saline solution exhibited poor tribological phenomenon compared with PBS bio-lubricant. The silicon nitride and ZTA showed better tribological behaviour for PBS bio-lubricant thus proving as potential materials for joint replacement in combination with AZ31.