低温合成碳化物过渡层对金刚石膜生长的作用机理研究

发布时间：2018-06-05 20:18

本文选题：金刚石薄膜 + 中频磁控溅射　；参考：《中国地质大学(北京)》2016年博士论文

【摘要】：在硬质合金与金刚石薄膜之间添加碳化物过渡层是制备高质量金刚石薄膜,提升星际钻探等领域工具使用性能的有效方法。目前常用的高温化学气相沉积(CVD)过渡层制备方法存在界面粗化和高热应力等问题,会导致过渡层使用效果和金刚石薄膜性能的降低。探索低温沉积碳化物过渡层方法是改善硬质合金金刚石涂层界面性能的重要前沿课题。本论文在评述硬质合金金刚石涂层研究进展和热点问题的基础上,以碳化物金刚石过渡层的低温沉积方法为核心,以中频磁控溅射和离子注入方法为手段,进行了硬质合金表面Si、Ti碳化物过渡层的低温制备及性能研究,并探索了过渡层制备工艺对金刚石涂层的影响。通过对薄膜成分、结构和结合性能等方面的系统考察,分析了制备工艺和薄膜性能的交互关系,从而揭示了沉积工艺对碳化物过渡层和金刚石薄膜的影响规律,探讨了碳化物过渡层影响金刚石薄膜形核、生长和性能的作用机理。本研究试图获得效果显著、重复性好的碳化物过渡层低温沉积方法和工艺设计,制备性能优异的硬着合金金刚石涂层工具,拓展硬质合金工具在星际钻探和特种加工等领域的应用范围。本文通过大量实验和分析测试,取得了如下的研究成果:1.采用中频磁控溅射技术在不同沉积温度、偏压、靶电流和反应气体流量下制备了SiC过渡层,考察了工艺条件变化对SiC过渡层表面形貌、成分、组织结构及附着性能等方面的影响。结果表明:沉积温度、偏压、靶电流和反应气体(C2H2)流量的变化会对SiC膜层的表面形貌、成分等产生规律性的影响,通过对工艺参数的调控,可以实现对SiC膜层结构、成分、性能等方面的控制,获得适合金刚石形核、生长与性能提升的过渡效果。2.采用HFCVD技术在不同工艺参数下的SiC过渡层样品表面沉积了金刚石薄膜,分析研究了SiC过渡层表面组织形貌、缺陷、膜层成分及相结构对金刚石薄膜形核、生长及性能等方面的影响规律。结果表明:SiC过渡层的组织缺陷、成分和相组成会显著影响金刚石的形核及膜层性能,致密度高、Si和C元素比接近1:1、β-SiC含量高的SiC过渡层更有利于获得高质量的金刚石薄膜。β-SiC过渡层对金刚石形核和膜层质量提升具有重要的促进作用,其对金刚石形核的作用过程可以分为六个阶段:形核准备阶段、原子活化阶段、原子替换阶段、晶核形成阶段、晶核生长阶段、膜层扩展阶段。3.采用离子注入方法在硬质合金表面制备了TiC薄层,系统分析了Ti离子在不同的注入能量下对硬质合金样品表面形貌、成分等方面的影响和对金刚石形核、生长及性能方面的影响。结果表明:Ti离子注入能量的变化会对硬质合金表面TiC薄层的成分、结构和性能产生规律性的影响,在注入能量为35 KV时可以获得较理想的效果,该膜层能够更好地促进金刚石的形核并获得附着性能良好的金刚石薄膜。
[Abstract]:The addition of carbide transition layer between cemented carbide and diamond films is an effective method to prepare high quality diamond films and improve the performance of tools in interstellar drilling. Some problems such as interface coarsening and high thermal stress exist in the common methods of preparing transition layer of high temperature chemical vapor deposition (CVD), which will lead to the decrease of the effect of the transition layer and the performance of diamond film. Exploring the method of low temperature deposition of carbide transition layer is an important frontier issue in improving the interfacial properties of cemented carbide diamond coatings. Based on the review of the research progress and hot issues of cemented carbide diamond coatings, the low temperature deposition method of carbide diamond transition layer and the method of intermediate frequency magnetron sputtering and ion implantation are taken as the core of this paper. The low temperature preparation and properties of Si-Ti carbide transition layer on cemented carbide surface were studied, and the effect of transition layer preparation process on diamond coating was explored. Based on the systematic investigation of the composition, structure and bonding properties of the films, the interaction between the preparation process and the properties of the films was analyzed, and the influence of the deposition process on the carbide transition layer and the diamond film was revealed. The mechanism of effect of carbide transition layer on nucleation, growth and properties of diamond films was discussed. The aim of this study is to obtain the effective and reproducible low temperature deposition method and process design of carbide transition layer, and to prepare hard alloy diamond coating tools with excellent performance. Expand the application of cemented carbide tools in interstellar drilling and special processing. In this paper, through a large number of experiments and analytical tests, we have obtained the following research results: 1. 1. SiC transition layer was prepared by intermediate frequency magnetron sputtering at different deposition temperature, bias voltage, target current and reactive gas flow rate. The surface morphology and composition of SiC transition layer were investigated by changing the process conditions. The influence of structure and adhesion. The results show that the changes of deposition temperature, bias voltage, target current and reactive gas flow rate will have regular effects on the surface morphology and composition of SiC film. The structure and composition of SiC film can be realized by adjusting the process parameters. The transition effect of diamond nucleation, growth and performance was obtained by controlling the properties of diamond. Diamond films were deposited on the surface of SiC transition layer samples with different process parameters by HFCVD technique. Microstructure, defects, film composition and phase structure of SiC transition layer were studied to nucleate diamond films. The effect of growth and performance. The results show that the microstructure defect, composition and phase composition of the transition layer of 1: sic can significantly affect the nucleation and film properties of diamond. The SiC transition layer with high density of Si and C is more advantageous to obtain high quality diamond films than the SiC transition layer with high content of 尾 -SiC. The 尾 -SiC transition layer plays an important role in promoting the nucleation and quality improvement of diamond films. The process of nucleation of diamond can be divided into six stages: nucleation preparation stage, atomic activation stage, atomic substitution stage, nucleation growth stage, film expansion stage. TiC thin layer was prepared on cemented carbide surface by ion implantation method. The effects of Ti ion on surface morphology and composition of cemented carbide samples and diamond nucleation were systematically analyzed at different implantation energies. Growth and performance effects. The results show that the composition, structure and properties of the TiC thin layer on the cemented carbide surface can be affected regularly by the change of the energy of the implanted ion. The ideal effect can be obtained when the implantation energy is 35 KV. The film can better promote diamond nucleation and obtain diamond films with good adhesion.
【学位授予单位】：中国地质大学(北京)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG174.4

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