Superior antiwear biomimetic artificial joint based on high-entropy alloy coating on porous Ti6Al4V

摘要

The wear of the currently available artificial joints is unavoidable, and the long-term stability needs to be improved. However, the performance of the existing artificial joints suffers from high friction coefficient, large modulus difference and poor connectivity. In this study, a dual coupling bionic artificial joint structure exhibiting antiwear, toughness and high connectivity was developed, which effectively reduced the joint material friction coefficient without biological toxicity. The structure consisted of porous Ti6Al4V and high-entropy alloy coating with superior hardness. Both reciprocating friction test and fluid simulation analysis revealed significant anti wear performance of the structure, which was closely dependent on the pore size. The ball-disc reciprocating friction analysis under dry and biotic environmental conditions lead to a reduction of 37% and 35.7% respectively in the friction coefficient by employing the high-entropy alloy coating. The wear loss was the lowest in the case of 30 ?m diameter of the pore-forming agent, as revealed through the fluid simulation of the structure. It is anticipated that the coupled biological artificial joint structure will prolong the service life of the artificial joints and provide a new alternative for clinical joint replacement.