SBIR Phase II: Nanocrystalline Diamond Coated Cutting Tools

该小型企业创新研究（SBIR）第二阶段项目将在碳化钨切削工具上开发纳米晶金刚石涂层，其技术属性超过当前一代化学气相沉积（CVD）金刚石涂层以及由多晶金刚石（PCD）晶片制成的工具。用于切削工具的CVD金刚石涂层的问题是表面光洁度差和附着力弱。使用微波等离子体（MP）技术沉积的纳米晶CVD金刚石克服了这些问题，具有良好粘附的光滑光洁度。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30千瓦的MP-CVD反应器来研究纳米晶结构和技术性能之间的关系。该结构将由工艺变量控制。技术性能将通过机械测试和现场测试来测量，用于加工铸造铝硅合金的拟议目标应用。预期的技术结果将是结构、性能和性能之间的直接相关性，其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，这是由于在切削工具工业中的应用促进了难以精加工的先进材料的使用;在纸浆和纸张中用于切割和导向，在纺织品中用于导向，以及在各种轴承表面应用中的应用，例如深井石油钻头轴承。国家卫生研究所还赞助了纳米晶体金刚石在生物医学硬件表面磨损方面的应用研究。此外，切削液和加工过程中产生的相关废物对环境的影响正在推动制造商实施干式加工工艺。MP-CVD纳米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.