NSF Award
9531815
*** 9531815 Stiglich This Small Business Innovation Research Phase II Project will develop a commercially viable nano grained tungsten carbide composite for dies, cutting tools, drills and reamers, and drill bit inserts applications. Phase I results were generally successful in demonstrating that 50-100 nm WC grains could be dispersed in a 6 wt% Co matrix by solution chemistry. The resulting powder, along with commercial "submicron" WC/ 6 wt% Co powders from three cutting tool companies, was consolidated by five different pressure assisted processes. Four of them were "fast" - total process time densified all of the powders to 97% to 100% of theoretical density. Microhardness data were compared among several commercial materials with the proposed material being the hardest at 2300 Vickers vs. 1600 to 1800 for commercial materials. Phase II will accomplish the following objectives. Commercial viability will be established by working with several industrial partners. A WC/Co composition will be developed including grain growth inhibitors (such as VC) which will be suitable for extrusion and sintering while maintaining the WC grain size achieved in Phase I. Physical properties such as transverse rupture strength, fracture toughness, and wear resistance will be related to WC grain size and consolidation parameters. Cutting tools of various types will be fabricated for commercial evaluation. There are many wear parts, tool and die, and metal cutting applications for commercial carbide materials. Besides single point tools there are miniatures (down to 250 to 500 micron diameter) drills, reamers, etc. which are important for machining microcircuit boards. ***
