具有碳纤维热扩散层的层状陶瓷刀具制备机理及其切削性能研究

Laminated ceramic cutting tool showed excellent cutting performance in machining difficult-to-machine materials. However, the fabrication efficiency of the laminated ceramic cutting tool is low, the size of the ceramic layer is not easy to control and the heat transfer performance and thermal shock resistance of the cutting tool are necessary to further improve. A new fabrication technology of atomize–spray liquid membrane–dry method and a new additive of carbon fibers will be employed in this investigation to improve the current situation of the laminated ceramic cutting tool in fabrication process and practical application. Stratification mechanism of the ceramic layer will be explored. Heat transfer performance and thermal shock resistance mechanisms of thermal diffusion layers will be investigated. Thermal diffusion layers are composed of carbon fibers flakes to improve the heat transfer performance and thermal shock resistance of the cutting tool. A model for efficiently fabricating the laminated ceramic cutting tool wil be established according to effects of sintering parameters, compositions of ceracmic, thickness of layer and distributions of carbon fibers flakes on cutting performance of laminated ceramic cutting tools in machining difficult-to-machine materials. The superiority of cutting performances of these cutting tools will be shown through machining difficult-to-machine materials. The results of this research lay a theoretical foundation for developing new layered ceramic cutting tools and have practical guiding significance for machining difficult-to-machine materials.

层状陶瓷刀具在切削难加工材料方面展现出优异的切削性能，但其制备效率低、层厚难以控制且刀具的热传导性及抗热震性还需要进一步改善。本研究提出雾化-喷覆液膜-干燥法制备层状陶瓷刀具材料新工艺，研究其成层机理，提高其制备效率，实现层厚的定量控制；通过向陶瓷体中添加碳纤维片体形成热扩散层，改善其热传导性和抗热震性，研究热扩散层的形成机制及其抗震机理；研究热压烧结工艺、陶瓷材料组分、层厚和碳纤维分布形态对层状陶瓷刀具切削性能的影响，并建立其关系模型，实现层状陶瓷刀具的高效制备；研究新型层状陶瓷刀具的切削性能，展现其在切削难加工材料时的优越性。本项目的研究结果将为新型层状陶瓷刀具的制备奠定理论基础，对难加工材料的加工具有实际指导意义。

本项目以制备高性能陶瓷刀具为目标，提出并系统地研究了雾化-喷覆液膜-干燥法制备层状陶瓷刀具材料素坯的新工艺，确定了其制备工艺参数；采用热压烧结技术对所制备素坯进行了烧结实验，确定了其烧结参数，并对烧结后的层状陶瓷刀具材料的微观组织和力学性能进行了研究，结果表明采用新工艺可实现不同陶瓷材料间的有效分层，材料的断裂韧度提高明显；在此基础上制备了含有碳纤维编织层的陶瓷刀具材料、含有短切碳纤维的陶瓷刀具材料和不含碳纤维的陶瓷刀具材料，并对所制备陶瓷刀具材料的微观组织和力学性能进行了研究，制备出多种新型高性能陶瓷刀具，其在切削难加工材料方面显示出优良的性能。在本基金的资助下，本项目取得了一系列的研究成果，已发表外文论文5篇，中文核心论文8篇，申请专利7项；培养研究生9名，其中3名已获硕士学位，4名硕士研究生在读，2名博士研究生在读。项目投入经费25万元，支出21.3793万元，各项支出基本与预算相符，剩余经费计划用于本项目研究的后续支出。