This Small Business Innovation Research (SBIR) Phase II project aims to develop a novel, commercially-viable, hybrid system that improves the adhesion of nanocrsytalline diamond (NCD) coatings to tungsten carbide (WC) cutting tools. A new hybrid system will be assembled, tested, and optimized. Research will be conducted to scale up the process to reach the capability of coating more than 3,000 cutting tools at one time. Further research will be conducted through laboratory and industrial machinability testing on these diamond-coated micro end mills. Testing variables include tool size, tool geometry, machining parameters (cutting speed, axial depth of cut, feedrate), workpiece material and environmental conditions. Industrial feedback will be used to ensure coating optimization to meet the needs of real users.
The broader/commercial impacts of this project will be the potential to significantly improve the performance of micro tools. An important area of this industry is currently limited by poor micro end mill performance. Improved tooling performance will not only reduce the capital machine cost in this field, but also help realize the miniaturization of existing cutting-edge technology limited by current manufacturing capabilities. The most promising societal benefits of NCD tool coating will be realized in healthcare industry as diamond coatings are essential for the development of next generation biosensors and biomedical devices. This will significantly improve the quality and substantially reduce costs associated with biological sample testing, reducing the financial burden of healthcare expenses on individuals and the country.
NSF grant number 1127516, "Improving the Adhesion of Nanocrystalline Diamond to Micro Tools" resulted in the commercialization of three products, including two different types of diamond coatings for tools and another diamond-like coating for tools and other substrates. The ability to effectively coat micro sized tools with a thin diamond film is an important area of technological advancement that will have a trickle-down effect on a variety of industries through facilitating the innovation and production of new smaller products with increased functionality. The trend towards smaller more functional parts and systems is growing, but it is limited by the manufacturing processes needed to create the small parts, including micro machining processes. When it comes to actually designing and fabricating a new micro part or system, many factors have to be considered and overcome before commercial manufacturing is feasible. Thin diamond coatings for tooling is helping to overcome some of these hurdles. For example, diamond coatings improve the machining quality (less tool run-out or burr formation), which can translate into the ability to make finer and finer parts that would be un-attainable with an un-coated tool. Diamond coatings can also allow a tool to last significantly longer, or to remove the material being machined significantly faster, both of which translate into making a prototype part a reality. Furthermore, thin diamond film manufacturing is a platform technology that has many possible applications beyond the tooling industry. Diamond thin film engineering is becoming a very desirable technology to harness because of diamondâ€™s optimal properties (hardness, biocompatibility, low coefficient of friction, heat conductivity, optical properties, etc.) Therefore, fundamental research into the growth and fine-tuning of diamond films has further value than just in the tooling industry. Research and development performed under the NSF grant has allowed a much more robust understanding of the underlying principles controlling diamond growth on a variety of materials, which will translate into improvement of many different devices/parts in a variety of industries in the future.