The study explores the tribocorrosive behavior of biocomposites based on high-density polyethylene (HDPE) reinforced with squid feather (SP) particles in contact with Ti6Al4V pins in a bovine serum solution. Tribocorrosion tests were carried out on biocomposites containing different mass fractions of SP (0, 5, 10, and 15 wt.%) to assess the influence of this reinforcement on wear resistance and electrochemical interactions at the composite–metal interface. The results show that the addition of 5 wt.% SP reduces the coefficient of friction by 13% and decreases the specific wear rate by 30% compared to pure HDPE, which correlates with efficient repassivation of the Ti6Al4V surface in the presence of albumin. On the other hand, the incorporation of 10 and 15 wt.% SP leads to an increase in the coefficient of friction of 4% and 44% respectively, as well as a 7% increase in the specific wear rate for 15 wt.% SP, due to a more marked de-passivation of Ti6Al4V and an increase in surface roughness.
