Tribological characterization of coatings and nanofluids
Baxi, Juhi Bhaskar
MetadataShow full item record
Advancement in biotechnology has successfully converted the conventional bearing couples into artificial joints. Materials used today, however, have not been satisfactory. Problems such as osteolysis and aseptic loosening lead to failure of artificial joints and also the lifespan of these joints is to be further improved. This research targets two issues related to the problem: coatings and design of new generation biofluids. Superior to metals and polymers, ceramics are hard and biocompatible and exhibit low wear and friction. The ceramic-on-ceramic bearing pair could last for a long time which could be beneficial to younger and active patients who need a bearing pair which would last for more than 15 years to avoid the possibility of a revision surgery. The first part of this thesis deals with studying the microstructure-property relationship of new ceramic-based materials and coatings. Specifically, alumina (ceramic) coatings at different current intensities were tested in order to determine their feasibility as a biomaterial for artificial joints. In order to find a new avenue for developing biofluids, the second part of this thesis focuses on the failure of artificial joints under inadequate lubrication. Also due to osteoarthritis, synthetic biofluid is injected into joints to help relieve pain but it works for only 6-9 months. We propose a new method using noble gold nanoparticles to modify fluids. This was accomplished by mixing different concentration of nanoparticles with biofluid. This thesis consists of 6 sections. The first section is an introduction to tribology, biotribology and artificial joints which is followed by the second section which discusses the objectives of the research. The third section describes the materials and methods used in the research. The tribological characterization of MAO alumina coatings is discussed in the fourth section and the fifth section discusses the effect of nanoparticles on fluid lubrication. The last section is the conclusion.