Abstract This proposed two-year diversity research supplement funding request to active National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) grant (1R01 AR078241) in response to PA- 21-071 aims to test our central hypothesis that CaP based solid lubricants in Ti or CoCrMo alloys will form an in situ films at the contact surface to minimize bio-tribo-corrosion and reduce metal ion release. The rationale is that once we understand the mechanisms of tribofilm formation and its influence on bio-tribo-corrosion, we can design implants with reduced metal ion release possibility in vivo. Our preliminary data show in situ tribofilm formation with CaP reinforcement in Ti6Al4V or CoCrMo alloys during in vitro bio-tribo-corrosion studies. The presence of tribofilm lowered wear-induced damage and minimized metal ion release in vitro. Our program will address the knowledge gap – understanding bio-tribocorrosion mechanism for surfaces with in situ formed tribofilms in CaP reinforced Ti or CoCrMo alloys to replace CoCrMo femoral head in THA. Moreover, the inherent ductility of CaP reinforced composite implants will eliminate any concerns related to the possibility of brittle fracture common in alumina-based ceramic heads that are currently being used as an alternative to CoCrMo. Our effort will also focus on translating laser-based 3D Printing (3DP) technology toward processing these novel composites. The proposed two-year diversity research supplement is requested for Dr. Jose Avila for his post- doctoral research work on 3D Printing of femoral heads using Ti6Al4V reinforced with CaP and a hard ceramic phase and test them using a hip simulator to measure both the wear-induced damage and bio- corrosion. The clinical success of this supplemental research is in manufacturing innovative femoral heads with CaP, and ceramic phase added Ti6Al4V alloy composites via 3D Printing as an alternative to pure CoCrMo. These composites will eliminate Co and Cr ions leaching due to corrosion and wear degradation from the trunnions of modular taper interlocks in THA, which leads to ALTR and early revision surgeries.