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Effect of cathode composition on microstructure and tribological properties of TiBN nanocomposite multilayer coating synthesized by plasma immersion ion implantation and deposition

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Journal of Central South University 2017年第10期24卷 2238-2244页

作者： Lü Wen-quan CAO Yong-zhi WANG Lang-ping WANG Xiao-feng GU Zhi-wei YAN Yong-da YU Fu-li State Key Laboratory of Advanced Welding&Joining(Harbin Institute of Technology) Harbin 150001China Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

Nanocomposite multilayer TiBN coatings were prepared on Si(100) and 9Cr18Mo substrates using TiBN composite cathode plasma immersion ion implantation and deposition technique(PIIID). Synthesis of TiBN composite cathodes was conducted by powder metallurgy technology and the content of hexagonal boron nitride(h-BN) was changed from 8% to 40%(mass fraction). The as-deposited coatings were characterized by energy dispersive spectrometer(EDS), grazing incidence X-ray diffraction(GIXRD), Fourier Transform Infrared Spectroscopy(FTIR) and high resolution transmission electron microcopy(HRTEM). EDS results show that the B content of the coatings was varied from 3.71% to 13.84%(molar fraction) when the composition of the h-BN in the composited cathodes was changed from 8 % to 40%(mass fraction). GIXRD results reveal that the TiBN coatings with a B content of 8% has the main diffraction peak of TiN(200),(220) and(311), and these peaks disappear when the B content is increased. FTIR analysis of the multilayer coatings showed the presence of h-BN in all coatings. TEM images reveal that all coatings have the characteristics of self-forming nanocomposite multilayers, where the nanocomposites are composed of face-centered cubic Ti N or h-BN nanocrystalline embedded in amorphous matrix. The tribological tests reveal that the Ti BN coatings exhibit a marked decrease of coefficient at room temperature(~0.25). The improved properties were found to be derived from the comprehensiveness of the self-forming multilayers structure and the h-BN solid lubrication effects in the coatings.

关键词： TiBN coatings nanocomposite multilayer plasma immersion ion implantation and deposition

Structure and Tribological Property of TiBN Nanocomposite Multilayer Synthesized by Ti-BN Composite Cathode Plasma Immersion Ion Implantation and Deposition

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Chinese Physics Letters 2016年第9期33卷 73-76页

作者：吕文泉王浪平曹永志顾至伟王小峰闫永达于福利 State Key Laboratory of Advanced Welding & Joining Harbin Institute of Technology Centre for Precision Engineering Harbin Institute of Technology

A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiBN coating shows a self-forming multilayered nanocomposite structure while with relative uniform elemental distributions. High resolution transmission electron microscopy images reveal that the multilayered structure is derived from different grain sizes in the nanocomposite. Due to the existence of h-BN phase, the friction coefficient of the coating is about 0.25.

关键词： of in is BN Structure and Tribological Property of TiBN Nanocomposite Multilayer Synthesized by Ti-BN Composite Cathode Plasma Immersion Ion Implantation and Deposition by Ti

The coupling effect of slow-rate mechanical motion on the confined etching process in electrochemical mechanical micromachining

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Science China Chemistry 2018年第6期61卷 715-724页

作者： Lianhuan Han Yuchao Jia Yongzhi Cao Zhenjiang Hu Xuesen Zhao Shusen Guo Yongda Yan Zhongqun Tian Dongping Zhan Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of Technology Center for Precision Engineering Harbin Institute of Technology State Key Laboratory of Physical Chemistry of Solid Surfaces (PCOSS) Collaborative Innovation Centre of Chemistry for Energy Materials(iChEM) and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University

By introducing the mechanical motion into the confined etchant layer technique(CELT), we have developed a promising ultraprecision machining method, termed as electrochemical mechanical micromachining(ECMM), for producing both regular and irregular three dimensional(3 D) microstructures. It was found that there was a dramatic coupling effect between the confined etching process and the slow-rate mechanical motion because of the concentration distribution of electrogenerated etchant caused by the latter. In this article, the coupling effect was investigated systemically by comparing the etchant diffusion, etching depths and profiles in the non-confined and confined machining modes. A two-dimensional(2 D) numerical simulation model was proposed to analyze the diffusion variations during the ECMM process, which is well verified by the machining experiments. The results showed that, in the confined machining mode, both the machining resolution and the perpendicularity tolerance of side faces were improved effectively. Furthermore, the theoretical modeling and numerical simulations were proved valuable to optimize the technical parameters of the ECMM process.

关键词： confined etchant layer technique electrochemical micromachining coupling effect mechanical motion confined etching

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基于约束刻蚀原理的电化学微纳加工研究进展

中国科学：化学 2017年第5期47卷 594-602页

作者：韩联欢何权烽赵学森曹永智胡振江闫永达田昭武詹东平固体表面物理化学国家重点实验室能源材料化学协同创新中心厦门大学化学化工学院化学系厦门361005 哈尔滨工业大学精密工程研究所哈尔滨150001

与机械加工相比,电化学加工技术具有无刀具磨损、无热效应、无机械损伤、加工效率高等优点,而且适用于柔性、脆性及超硬材料,具备传统方法难以实现的复杂结构加工能力,因而在航空航天、汽车、微电子等领域有着重要应用,日益成为一种重... 详细信息

与机械加工相比,电化学加工技术具有无刀具磨损、无热效应、无机械损伤、加工效率高等优点,而且适用于柔性、脆性及超硬材料,具备传统方法难以实现的复杂结构加工能力,因而在航空航天、汽车、微电子等领域有着重要应用,日益成为一种重要的工业制造技术.随着超大规模集成电路(ULSI)、微机电系统(MEMS)、微全分析系统(μ-TAS)、现代精密光学系统等高技术产业的迅速发展,功能性结构/器件的微型化和集成化的要求越来越高.由于传统电化学只适用于金属材料,为了应对微纳制造的时代要求,拓展电化学加工的材料普适性,1992年田昭武院士提出了具有我国自主知识产权的约束刻蚀剂层技术(CELT).一般的,约束刻蚀包括3个步骤:(1)通过电化学、光化学或光电化学的方法在模板电极表面生成刻蚀剂;(2)通过后续的均相化学反应或自由基衰变反应将刻蚀剂约束在微/纳米厚度的液层内;(3)将模板电极逼近加工基底,当约束刻蚀剂层接触被加工基底时,通过刻蚀反应实现微纳加工.最近,联合课题组通过仪器、原理和方法3个方面的努力,引入外部物理场调制技术,实现一维铣削、二维抛光、三维微/纳结构加工,大幅提升了CELT的技术水平.

关键词：电化学微纳加工电化学加工约束刻蚀剂层技术外场调制电极过程动力学