Structuring Superhard Surfaces for Resisting Wear
More than 50,000 total and partial joint replacements are performed in Canada each year. The wear of the joint components leads to a loosening of the devices, which is a major cause of device failure, limiting joint lifetime. Wear is also the major failure mechanism limiting the lifetime of tools and machine parts. Thus increasing resistance to wear is key to improving the durability and performance of artificial joints as well as tools and machine parts and that is Dr. Qiaoquin Yang's objective as a Canada Research Chair.
Surface coating is emerging as an important technology for reducing wear and extending performance of materials. In collaboration with Canada Research Chair Professor A. Hirose, Dr. Yang has already come up with several novel wear resistant coatings (e.g., Ti-B-N, diamond). Recently, she has also developed a technology that enables synthesis of carbon films (including carbon nanotube, nanocrystalline diamond, and diamond and graphitic nanocone) with controlled nanostructures (controlled shapes, sizes, crystallographic structure, distributions, and orientations).
Now, as the Canada Research Chair in Nanoengineering Coating Technologies, Dr. Yang is using these nanostructured carbon films as a base to create novel nanoengineered composite coatings with a combination of superhardness and high-toughness for increasing wear resistance. These new composite coatings are expected to have high corrosion resistance and high biocompatibility to satisfy the requirements for biomedical implants.
Her research focuses on devising new technologies and design methods for structuring superhard surface coatings at the molecular level in order to achieve specific macroproperties (for example, greatly enhanced fracture toughness and adhesion). Applications of her work include wear protection for various tools, machine parts, magnetic storage media, and biomedical implants, leading to much improved tools, machine parts, and artificial joints, which in turn will increase manufacturing efficiency and improve health care.