SBIR Phase II: Nanocrystalline Diamond Coated Cutting Tools

这个小企业创新研究（SBIR）二期项目将开发用于碳化钨切削工具的纳米金刚石涂层，其技术属性将超过当前一代化学气相沉积（CVD）金刚石涂层以及由聚晶金刚石（PCD）晶圆制成的工具。刀具用CVD金刚石涂层的问题是表面光洁度差，附着力弱。利用微波等离子体（MP）技术沉积纳米晶CVD金刚石克服了这些问题，具有良好的粘附性和光洁度。这使得纳米晶金刚石通过降低价格和提高生产率而成为PCD金刚石的潜在竞争对手。第二阶段的研究将使用一个30kW的MP-CVD反应器来研究纳米晶体结构与技术性能之间的关系。结构将由过程变量控制。技术性能将通过机械测试和对拟加工铸铝硅合金目标应用的现场测试来衡量。预期的技术结果将是结构、性能和性能之间的直接相关性，可用于优化用于加工汽车传动系统部件的纳米晶金刚石涂层。纳米晶金刚石涂层的商业应用是深远的，因为它在刀具工业中的应用促进了难以加工的先进材料的使用；应用于纸浆和纸张的切割和导向，应用于纺织品的导向和应用于各种轴承表面的应用，如深井石油钻头轴承。美国国立卫生研究院也在资助纳米晶体金刚石在易磨损的生物医学硬件表面的应用研究。此外，加工过程中切削液和相关废物对环境的影响促使制造商实施干式加工工艺。MP-CVD纳米晶金刚石刀具是干式加工有色金属材料的理想刀具。

This Small Business Innovation Research (SBIR) Phase II project will develop nanocrystalline diamond coatings on tungsten-carbide cutting tools with technical attributes that surpass the current generation of chemical vapor deposited (CVD) diamond coatings as well as tools made from polycrystalline diamond (PCD) wafers. The problem with CVD diamond coatings for cutting tools is poor surface finish and weak adhesion. Nanocrystalline CVD diamond deposited using microwave plasma (MP) techniques overcomes these problems with a smooth finish that is well adhered. This makes the nanocrystalline diamond a potential competitor to PCD diamond by lowering the price and increasing productivity. The research proposed for Phase II will use a 30kW MP-CVD reactor to investigate the relationships between nanocrystalline structure and technical performance. The structure will be controlled by process variables. Technical performance will be measured by mechanical testing and field testing on the proposed target application of machining cast aluminum-silicon alloy. The anticipated technical result will be direct correlations between structure, properties and performance that can be used to optimize nanocrystalline diamond coatings for machining automotive drive-train components.Commercial applications of nanocrystalline diamond coatings are far reaching due to applications in the cutting tool industry that promote the use of hard-to-finish advanced materials; applications in pulp and paper for cutting and guides, applications in textiles for guides and applications in various bearing surface applications such as deep-well oil drill-head bearings. The National Institute of Health is also sponsoring research on nanocrystalline diamond applications in biomedical hardware surfaces subject to wear. Additionally, environmental impact of cutting fluid and related waste from machining processes are driving manufacturers to implement dry machining processes. MP-CVD nanocrystalline diamond tooling is the ideal tool for dry machining nonferrous materials.