A New Strategy for the Design of Wear Resistant Nitride Coatings for Dry Machining

该奖项的研究目标是研究切削刀具涂层的新概念，使钢和其他难以切削的金属合金能够进行干式高速加工。 该方法是设计涂层，耐高温氧化和扩散为基础的磨损机制。 现有技术的涂层主要基于其抗氧化性而得到推广。 使用在待加工工件内具有有限溶解度的大金属氮化物化合物将实现对基于扩散的磨损机制的抵抗。 由于高速加工操作受到氧化和扩散磨损，多层涂层的结构作为交替层的大金属氮化物与抗氧化氮化物将进行研究。 将这些涂层沉积为纳米级多层膜也将提高涂层的硬度和抗断裂性。 还将进行溅射沉积和沉积涂层的全面化学和机械表征。 将进行研究，以评估这些涂层在高速车削钢时的性能。 该研究的社会效益将通过推广干式加工代替润滑加工来实现。 使用切削液的加工操作引起了环境和健康方面的关注。 切削液的处理已变得更加规范，因此金属切削行业的成本更高。 在这项研究中要检查的涂层的成功将能够大大减少润滑剂的使用量，并在某些情况下，在切削过程中完全消除切削液。

The research objective of this award is to investigate a new concept in coatings for cutting tools that will enable dry, high-speed machining of steels and other hard-to-cut metal alloys. The approach is to design coatings that are resistant to both high-temperature oxidation and diffusion-based wear mechanisms. Current state-of-the art coatings have been promoted based primarily on their oxidation resistance. Resistance to diffusion-based wear mechanisms will be achieved using large-metal nitride compounds that have a limited solubility within the work piece to be machined. Since high-speed machining operations are subject to both oxidative and diffusion wear, multilayer coatings that are structured as alternating layers of large-metal nitrides with oxidation-resistant nitrides will be investigated. Depositing these coatings as nano-scale multilayers will also enhance the hardness and fracture resistance of the coatings. Sputter deposition and full chemical and mechanical characterization of the deposited coatings also will be carried out. Research will be conducted to evaluate the performance of these coatings during high-speed turning of steel. The societal benefits of the research will be realized through the promotion of dry machining in place of lubricated machining. Both environmental and health concerns have been raised for machining operations that use cutting fluids. The disposal of cutting fluids has become more regulated and therefore more costly for the metal cutting industry. The success of the coatings to be examined in this study will enable a substantial reduction in the quantity of lubricant used, and in some cases complete elimination of cutting fluids during cutting.