SBIR Phase II: Synthesis of Nano Grained Tungsten Carbide Composite for Tools and Dies

这个小企业创新研究二期项目将开发一种商业上可行的纳米碳化钨复合材料，用于模具、切削工具、钻头和铰刀以及钻头刀片。第一阶段的结果通常成功地证明了50-100 nm的WC颗粒可以通过溶液化学分散在6 wt% Co基体中。由此产生的粉末，以及来自三家刀具公司的商业“亚微米”WC/ 6 wt% Co粉末，通过五种不同的压力辅助工艺进行巩固。其中四个是“快速”的——总工艺时间使所有粉末密度达到理论密度的97%到100%。将几种商业材料的显微硬度数据进行比较，建议材料的硬度为2300维氏，而商业材料的硬度为1600至1800维氏。第二阶段将完成以下目标。通过与几个工业伙伴合作，将建立商业可行性。将开发一种WC/Co组合物，包括晶粒生长抑制剂（如VC），它将适用于挤压和烧结，同时保持第一阶段WC的晶粒尺寸。物理性能，如横向断裂强度、断裂韧性和耐磨性将与WC晶粒尺寸和固结参数有关。各种类型的刀具将被制造用于商业评估。商用硬质合金材料有许多易损件、工具和模具以及金属切削应用。除了单点工具，还有微型（直径小至250至500微米）钻头，铰刀等，这些对于加工微电路板很重要。＊＊＊

*** 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. ***