A Ni/surface-modified Diamond Composite Electroplating Coating on Superelastic NiTi Alloy as Potential Dental Bur Design

摘要

Dental diamond bur is now a regular rotary tool, with its head made of diamond particles embedded into nickel coating, and its shank made of stainless steel. There are strong demands from the dentist on prolongation of usage life and avoiding of breakage. To solve this problem, on the one hand, since diamond is hard to be wetted under the condition of normal temperature and pressure due to the high interfacial energy between diamond and general metals and alloys. Diamond particles coated with titanium layer was used for the preparation of composite electroplating with the intention of improving the interfacial adhesion between diamond and metal matrix; on the other hand, superelastic biomedical NiTi alloy was used as the substrate to improve the flexibility and prevent the breakage. In this study, the optimal preparation parameters of Ni/surface-modified diamond electroplating were determined by orthogonal test, and the bonding conditions between the diamond particles and the NiTi alloy substrate were studied by scanning electron microscope. Further performance comparison of Ni/modified and Ni/un-modified diamond composite electroplating was conducted on a pin-on-disc wear machine under the dry sliding condition, and the material removal volume was used as the evaluating criterion of wear resistance. The results showed that the binding strength between diamond particles and NiTi alloy substrate could be enhanced, as well as the wear resistance, which may give direction on the future design of dental bur.