SBIR/STTR Award attributes
Cemented Tungsten Carbide is an important material for the USA and is used in a wide variety of products and manufacturing processes. The material is typically produced by mixing fine powders of WC with fine particle cobalt metal. Important applications are wear resistant manufacturing tooling such as die and punches, mining and roadway milling bits and machining inserts for milling and turning. Tungsten and Cobalt are both listed as critical materials that are strategically important to the United States yet are highly reliant on imports in the US supply chain. It would be a strategic advantage if the amount of Tungsten and Cobalt could be reduced by utilizing a material that exhibits properties as good as or better than WC. In the past ceramic material such as boron carbide or alumina toughened zirconia have been utilized but ultimately prove too brittle for most applications.Reductions of the amount of W and Co used in industrial and commercial applications can be realized by a combination of directly reducing the amount of strategically important materials required in a product and by increasing the life of the product. Using our novel synthesis route to create an alternative material for these applications, we propose to explore the super-hard material properties in comparison to WC, using a cemented binder system that does not contain cobalt. Millennitek has successfully synthesized a superhard material in a continuous process, suited for large volume industrial production. The goal is to manufacture this material and develop a cementation process that will yield a material with a hardness greater that 40 GPa and with a Transverse Rupture Strength that is the same or better than WC. The material should theoretically be more than 1.5x harder than WC, which could ultimately lead to a 50% reduction of required critical tungsten for the same wear rate of WC. Even if the same industry-standard cobalt binder system would be utilized to lower the risk of adoption, the project outcome could still have a significant effect on reducing critical tungsten materials in these applications. However, we intend to explore other cementation materials that are more readily available in the US to allow us to reduce reliance on Co. These materials will include Ni-Fe-Co binders in various single and combined combinations. Hardness, fracture toughness and wear testing will be performed on the material samples, and deliverables include small machined shapes to demonstrate feasibility of the technology to compete favorably with cemented WC tooling. In addition to tooling applications, there are other significant potential area’s where this material could be commercialized, including nuclear, aerospace, defense and other industrial areas. The material in its purest form is being explored as a potential gamma and neutron shield.
