PFI:AIR-TT: WC/Co Materials with High Hardness and Toughness Simultaneously Enabled by the WC Platelet Microstructure

Illinois Institute Of Technology, Chicago IL

Investigators

Abstract

This PFI: AIR Technology Translation project focuses on translating the discovery of Tungsten Carbide-Cobalt (WC/Co) materials with nano-WC platelets that offer characteristics of both high hardness and toughness to fill the needs of the hardmetal industry. This project will result in a sintering approach and processing conditions to obtain consistent and robust WC/Co materials with full densities and a uniform WC platelet microstructure simultaneously. These WC/Co materials with nano-WC platelets have the unique feature of thin WC platelets with high aspect ratios. This feature provides unprecedented enhancements in both hardness and toughness with properties better than any WC/Co materials known today. Such unmatched enhancements are achieved because thin thickness of nano-WC platelets offers high hardness, while the high aspect ratio provides superior toughness. In addition to the superior mechanical properties, this project also addresses the cost of WC/Co materials through our patented Integrated Mechanical and Thermal Activation (IMTA) process to make low cost nano-WC/Co powders as the starting materials to fabricate WC/Co materials with nano-WC platelets. This IMTA process combines mechanical and thermal activation to reduce processing steps, lower reaction temperatures, shorten reaction times, decrease ball milling times, and thus drastically reduce the cost of the nano-WC/Co powder. Currently, the roadblock to the anticipated potentials is inhomogeneous microstructure and a large variation in hardness and toughness. Thus, this PFI: AIR Technology Translation project will focus on sintering study and establish sintering conditions to attain consistent WC/Co materials with compositions ranging from 6 to 18 wt.% Co in conjunction with full densities and a uniform WC platelet microstructure simultaneously. The project engages Kennametal, the second largest WC/Co manufacturer in the world, to independently evaluate the mechanical properties of the WC/Co materials with nano-WC platelets with a goal to accelerate technology translation from research discovery toward commercial reality. In addition, the project team works with University Technology Park (UTP) at Illinois Institute of Technology. UTP is one of the nation's fastest-growing hubs for high-tech innovation, and has a robust network of venture capital firms and angel investors. Working with UTP offers the project team with the option of creating a startup company with funds from venture capital firms or angel investors as well as office space and laboratories required by a new startup company. The WC/Co materials with nano-WC platelets are important because WC/Co materials make up of 98% of all hardmetal components and have been widely used in military, aerospace, automotive, marine, petrochemical, mining, electronics, and wood industries. In all of these military and civilian applications, superior wear resistance derived from a combination of high hardness and high toughness is required. In some cases, impact resistance is also a must. Therefore, advanced WC/Co materials with simultaneous improvements in hardness and toughness will greatly enhance the performance of many existing WC/Co components, and open up new opportunities in areas outside their current application windows. The low cost manufacturing that we have developed can further propel widespread applications of such novel WC/Co hardmetals, and enhance the US manufacturing competitiveness.