【作者】 薛宏国；

【导师】 孙方宏；

【作者基本信息】 上海交通大学 ， 机械制造及自动化， 2007， 硕士

【摘要】 CVD金刚石薄膜涂层刀具是通过化学气相沉积(Chemical Vapor Deposition)在硬质合金刀具材料基体上沉积金刚石膜制备而成的。金刚石涂层刀具既具有很高的刀具耐磨性有具有良好的冲击韧性,涂层摩擦系数小,导热性能好,在高硅铝合金、金属基复合材料、有色金属、纤维增强聚合物层压制品等材料的切削加工领域应用前景十分广泛。该种刀具制造工艺相对简单,成本较低,尤其可以通过在刀具基体上直接沉积而制造复杂形状金刚石涂层刀具,如铣刀、钻头等,在难加工材料高速切削加工方面显示出极具潜力的应用前景。本文针对复杂形状CVD金刚石薄膜涂层刀具的制备技术及在切削加工中应用所涉及到的若干关键性技术问题,如提高基体表面形核率,改善金刚石薄膜与硬质合金刀具基体之间的附着强度和金刚石薄膜涂层刀具的切削加工应用等方面开展研究。1、对热丝CVD沉积金刚石薄膜的非平衡热力学耦合模型和动力学模型进行研究,重点分析热丝CVD沉积金刚石膜系统中衬底温度场分布及相关因素对于薄膜沉积质量和速率的影响,同时结合实验室所进行的金刚石薄膜制备实验中所获得的实验数据和检测结果,优化金刚石薄膜沉积工艺。2、研究适合复杂形状硬质合金刀具基体的预处理方法,对传统的酸碱二步预处理方法中的处理参数进行优化,得到可获得高形核密度的最优二步预处理参数。在更多还原

【Abstract】 Diamond coated cutting tools are prepared by depositing a diamond thin film on cemented carbide substrate with Chemical Vapor Deposition (CVD) method. Diamond coated cutting tools have unique combination of excellent physical properties, such as high hardness and toughness, good thermal conductivity, outstanding wear and chemical resistance and low friction coefficient, and have wide application potential in the machining of aluminum alloys with high silicon-content, metal matrix composite material, engineering ceramics, non-ferrous metals, and fiber reinforced plastics. The coating technology is relatively simple and cheap, and can be applied to cutting tools with complex shape, such as milling cutters, twist drills and taps etc., by depositing the diamond film on the substrate material directly, so that they can be employed to machine difficult-to-cut materials with high efficiency.The thesis aims at some key technological issues regarding on the deposition process of diamond coated cutting tools with complex shape and their application in machining, such as increasing the nucleation density in the beginning of diamond coating, improve the adhesive strength between the diamond film and the substrate, and the cutting performance evaluation.The main research contents of the thesis are as following:1. The non-equilibrium thermodynamics and the dynamics model of the diamond thin film deposition was studied; the temperature field distribution on the substrate in the reaction apparatus was computed; the role of the temperature field distribution and relevant factors in diamond film deposition quality and speed is analyzed; and the deposition process is optimized based on the inspect results and data of the diamond deposition experiments conducted in the lab.2. Pretreatment methods suitable for cemented carbide substrate with complex shape are investigated; the pretreatment parameters of the conventional two-step pretreatment process are optimized, and the optimal process parameters leading to high nucleation更多还原