Fabrication Of Bionic Micro And Nano Surface Structures Of Artificial Hip Joints By Laser Interference

The surfaces of the organisms in nature have a variety of special functions. The special texture formed in the evolutionary process of flora and fauna in nature gives mankind much inspiration, especially, the aspect of decreasing friction by texture arrays. Investigation of micro and nano surface structures of living beings and fabrication of bionic functional structures are the key research issues in biomimics.These issues have a wide range of potential applications in many fields such as industry, aerospace, military, medicine and daily life.This report studies the feasibility of using laser interference lithography for the surface modification of Co-Cr-Mo implant alloy which is commonly applied to the wear surface in the total joint replacement in medicine. Highly ordered micro structures were fabricated on the Co-Cr-Mo alloy surface. Different laser parameters were used to study the effects of them on the surface modification. The tribological performances and surface topography of the samples were studied by RTEC micro-friction and wear tester and scanning electron microscope(SEM). Hardness testing of the modified sample surfaces was carried out using micro-hardness tester(MH-60), and this work reports the result of biomaterial compatibility evaluation.Experimental results indicate that the sample surface modified with laser interference lithography presents better tribological performances and hardness properties than those untreated materials, including a 64% friction coefficient reduction and 40%hardness enhancement, and the laser processing does not change the inherent biocompatibility of the materials used to fabricate the structures. With the method developed in this project, the innovative total hip arthroplasty will be created which is very promising to significantly reduce the mean revision rate of post primary total hip replacements in the future.