Enhancing the fretting damage resistance of suspension plasma sprayed hydroxyapatite coating with Titania addition

The damage of the bioactive HAp ceramic coatings on titanium implants and debris generated at the implant stem-bone interface is a major concern as it causes osteolysis, metallosis, and loosening of implants. Attempts are made to develop strong and wear-resistant biocompatible HAp coatings through the addition of different ceramics and with better coating processes. The addition of titania to HAp was found to strengthen the coating, and this paper reports the fretting wear resistance of titania-added HAp suspension plasma spray coating. Expected micro motion between the stem-bone interface in the implants due to applied loads is estimated using numerical simulations. The fretting wear resistance of the titania-added coating was evaluated using the simulated ball-onflat contacts. The titania-added HAp suspension plasma spray-coated samples exhibited reduced fretting friction coefficient and increased wear resistance. High hardness and modulus of the 50 % titania added HAp contribute to the reduced fretting damage and wear debris generation at the interface.