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Research on the Characters of the Cutting Force in Vibration Cutting Particle Reinforced Metal Matrix Composites sic_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 74-75页

作者： LIU chuan-shao 1, ZHAO Bo 1,2, GAO Guo-fu 1, JIAO F eng 1 (1. Department of Mechanical Engineering, Jiaozuo Institute of Techno logy, Henan 454000, China 2. Institute of Mechanical Engineering, Shanghai Jiaotong University, Shanghai 200030, China)

In this paper, turning experiments of machining particle reinforced metal matri x composites(PRMMCs) sic p/Al with PCD tools have been carried out. The cutting force characteristics in ultrasonic vibration turning compared with that in com mon turning were studied. Through the single factor experiments and multiple fac tor orthogonal experiments, the influences of three kinds of cutting conditions such as cutting velocity, amount of feed and cutting depth on cutting force were analyzed in detail. Meanwhile, according to the experimental data, the empirica l formula of main cutting force in ultrasonic vibration turning was conclude d. According to the test results, the cutting force is direct proportion to cutt ing depth basically according to the relation between cutting force and other fa ctors, which is similar to that of common cutting, so is the feed rate, but the influence is not so big. The influence of cutting speed is larger than that of f eed rate on cutting force because the efficient cutting time increases in vibrat ion cycle with the increase of cutting speed, which causes cutting force to incr ease. The research results indicate: (1) Ultrasonic vibration turning possesses much lower main cutting force than that in common turning when adopting smaller cutting parameters. If using larger cutting parameters, the difference will inco nspicuous. (2) There are remarkable differences of cutting force-cutting veloci ty characteristics in ultrasonic vibration turning from that in common turning m ainly because built-up edge does not emerge in ultrasonic turning unlike common turning in corresponding velocity range. (3) In ultrasonic vibration cutting, t he influence of cutting velocity on cutting force is most obvious among thre e cutting parameters and the influence of feed is smallest. So adopting lower cu tting velocity and larger cutting depth not only can reduce cutting force effect ively but also can ensure cutting efficiency. (4) The conclusions are usefu

关键词： composite sic p/Al PCD tool ultrasonic vibrati on turning cutting force

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Solid state synthesis and structure of two novel polyoxometalates [(n-Bu)_4N]_4[M_6o_(19)][Ag_21_4](M=Mo,W)

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Chinese Journal of Chemistry 1996年第2期14卷 123-130页

作者： HOU,Hong-Wei XIN,Xin-QuanState Key Laboratory of Coordination Chemistry,Department of Chemistry,Nanjing University,Nanjing,Jiangsu 210093,ChinaYU,Kai-BeiChengdu Center of Analysis and Determination,Chinese Academy of Sciences,Chengdu,sic/man 610041,ChinaWANG,Zhe-Min LIU,Shi-Xiong HUANG,Jin-lingDepartment of Chemistry,Fuzhou University,Fuihou,Fujian 350002,China State Key Laboratory of Coordination Chemistry Department of Chemistry Nanjing University Nanjing Jiangsu 210093 China Chengdu Center of Analysis and Determination Chinese Academy of Sciences Chengdu Sichuan 610041 China Department of Chemistry Fuzhou University Fuzhou Fujian 350002 China

The reaction of [NH4]2[MO2S2],AgI and (n-Bu)4NBr in solid state produced the polyoxometalates [(n-Bu)4N]4[M6O19][Ag2l4] (1,M=Mo;2,M=W) which were structurally *** crystals of 1 and 2 are isomorphous,monoclinic,space group P221/c.1,a=1.6624(2),6=1.6699(3),c=1.7217(2) nm,(8=98.29(1)°,V =4.729(1) nm3,Z=2,R=0.040,Rw=0.037;2,a= 1.6636(3),6=1.6733(3),c=1.7190(3) nm,β=98.25(1)°,V=4.736(1) nm3,Z=2,R=0.038,Rw=*** results of the structure determination showed that the two compounds had the same structures whose skeletons are composed of [Ag2I4]2-and [M6O19]2-The difference of them and heteropolymetalate compounds synthesized in solution is that the title compounds contain cluster ion,heteropolymetalate and organic cations,while the latter is only composed of heteropolymetalate and organic cations.

关键词： Solid state synthesis coordination compound structure

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PVD溅射电流对sic纤维表面Ti_3Al涂层组织结构的影响

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稀有金属 2014年第3期38卷 379-385页

作者：王敏涓黄浩解川黄旭李臻熙北京航空材料研究院先进钛合金航空科技重点实验室北京100095

采用磁控溅射物理气相沉积(PVD)法在sic纤维表面进行Ti3Al涂层的制备,研究了该过程中PVD溅射电流对Ti3Al涂层组织结构的影响规律。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和原子力显微镜(AFM)对Ti3Al涂层的沉积率、组成物相、晶粒大... 详细信息

采用磁控溅射物理气相沉积(PVD)法在sic纤维表面进行Ti3Al涂层的制备,研究了该过程中PVD溅射电流对Ti3Al涂层组织结构的影响规律。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和原子力显微镜(AFM)对Ti3Al涂层的沉积率、组成物相、晶粒大小、组织结构和表面形貌等进行了观察与分析。研究结果表明,磁控溅射PVD法制得的Ti3Al涂层组成物相与靶材一致,但涂层生长择优取向发生了变化。随着溅射电流的增大,Ti3Al涂层沉积率提高,平均晶粒尺寸增大。此外,涂层的微观形貌为柱状晶组织,但随着溅射电流的增加,涂层表面因粒子溅射辐照温度的升高而升温,同时晶粒边界出现迁移,涂层生长由V型柱状晶生长向等轴柱状晶生长转变,最后形成致密组织。涂层粗糙度的变化与涂层晶粒尺寸和微观结构有关,因此Ti3Al涂层表面粗糙度随着溅射电流增加呈现出先增大后减小的规律。

关键词：溅射电流物理气相沉积 Ti3Al 组织结构

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An upgraded polymeric composite with interparticle chemical bonding microstructure toward lithium-ion battery separators with enhanced safety and electrochemical performances

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Journal of Energy Chemistry 2023年第9期84卷 402-413页

作者： Qian Zhao ling Ma Ye Xu Xiulong Wu Shuai Jiang Qiaotian Zheng Guang Hong Bin He Chen Li Wanglai Cen Wenjun Zhou Yan Meng Dan Xiao College of Mechanical Engineering Chengdu UniversityChengdu 610106SichuanChina Institute for Advanced Study Chengdu UniversityChengdu 610106SichuanChina Chongqing Academy of Metrology and Quality Inspection Chongqing 401121China Institute of New Energy and Low-Carbon Technology Sichuan UniversityChengdu 610065SichuanChina

A composite separator of sic/PVDF-HFP was synthesized for lithium-ion batteries with high thermal and mechanical *** from the nanoscale,high hardness,and melting point of sic,sic/PVDFHFP with highly uniform microstructure was *** polarization caused by barrier penetration was significantly *** to the Si-F bond between sic and PVDF-HFP,the structural stability has been obviously enhanced,which could suppress the growth of lithium(Li) ***,some 3D reticulated Si nanowires are found on the surface of Li anode,which also greatly inhibit Li dendrites and result in irregular flakes of Li ***,the shrinkage of 6% sic/PVDF-HFP at 150℃ is only 5%,which is notably lower than those of PVDF-HFP and *** commercial LiFePO_(4) cell assembled with 6% sic/PVDF-HFP possesses a specific capacity of 157.8 mA h g^(-1) and coulomb efficiency of 98% at 80℃.In addition,the tensile strength and modulus of 6% sic/PVDF-HFP could reach 14.6 and 562 MPa,*** a small deformation(1000 nm) and strong deformation recovery are obtained under a high additional load(2.3 mN).Compared with PVDF-HFP and Celgard2500,the symmetric Li cell assembled with 6% sic/PVDF-HFP has not polarized after 900 cycles due to its excellent mechanical *** strategy provides a feasible solution for the composite separator of high-safety batteries with a high temperature and impact resistance.

关键词： sic PVDF-HFP Composite separator Thermal stability Mechanical stability High safety battery

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黄孢原毛平革菌(Phanerochaete chrysosporium)的抗性转化

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四川大学学报（自然科学版） 2000年第S1期37卷 179-186页

作者：田聆张义正华西医科大学附一医院肿瘤生物治疗研究中心成都610041 四川大学生物工程系分子生物学实验室成都610064

作者描述了黄孢原毛平革菌抗性转化的经过和结果 .在测定黄孢原毛平革菌对G4 18和潮霉素的敏感性的基础上 ,将在实验室已经分离到的由黄孢原毛平革菌基因启动子所构建成的融合卡那霉素抗性基因质粒切为线状 ,用原生质体转化法将其转化... 详细信息

作者描述了黄孢原毛平革菌抗性转化的经过和结果 .在测定黄孢原毛平革菌对G4 18和潮霉素的敏感性的基础上 ,将在实验室已经分离到的由黄孢原毛平革菌基因启动子所构建成的融合卡那霉素抗性基因质粒切为线状 ,用原生质体转化法将其转化黄孢原毛平革菌 ,用浓度为 2 0 0 μg/mL的G4 18成功地筛选到 16个G4 18r 转化子 .在测定了这些G4 18r 转化子的抗性水平和稳定性的基础上 ,用PCR扩增G4 18r 转化子中融合卡那霉素抗性基因启动子片段和Southern杂交两种方法 ,对G4 18r 转化子进行分析和鉴定 .结果表明 :融合卡那霉素抗性基因以单个或串状重复的形式整合入黄孢原毛平革菌基因组中 .G4 18r 转化子的确定不仅可为建立黄孢原毛平革菌的转化系统提供选择标记基因 ,而且证明所分离的基因启动子在黄孢原毛平革菌中的功能 ,同时还证明了以Escherichiacoli为宿主菌 ,直接用基因启动子探针型载体分离真核生物的基因启动子是完全可行的 .实验结果还表明 ,由异源基因启动子构建的融合潮霉素抗性基因质粒 pAN7 1和 pCSN4 3不能转化黄孢原毛平革菌 .

关键词：黄孢原毛平革菌融合Kan^r基因 G418抗性转化

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超声法制备纳米sic颗粒增强AZ61镁基复合材料的显微组织

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中国有色金属学报 2009年第5期19卷 841-846页

作者：胡志闫洪聂俏凌李石保南昌大学先进成形制造及模具研究所南昌330031

采用高能超声方法制备纳米sic颗粒增强AZ61镁基复合材料,通过SEM和XRD技术对复合材料的微观组织和成分进行研究与分析。在Lennard-Jones势函数的基础上对超声分散纳米颗粒进行了理论探讨。结果表明:在超声作用下,质量分数为1%的纳米sic... 详细信息

采用高能超声方法制备纳米sic颗粒增强AZ61镁基复合材料,通过SEM和XRD技术对复合材料的微观组织和成分进行研究与分析。在Lennard-Jones势函数的基础上对超声分散纳米颗粒进行了理论探讨。结果表明:在超声作用下,质量分数为1%的纳米sic颗粒在AZ61镁合金中得到弥散分布;颗粒之间存在的范德华力使得颗粒连接在一起,范德华力与颗粒半径和颗粒间距离的关系表明:直径为100nm的sic颗粒之间最大的范德华力约为135nN,分散团聚纳米颗粒的最小压强约为17.2MPa。

关键词： AZ61镁合金纳米sic 超声振动显微组织

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Experimental and numerical analyses of high voltage 4H-sic junction barrier Schottky rectifiers with linearly graded field limiting ring

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Chinese Physics B 2014年第5期23卷 490-494页

作者：王向东邓小川王永维王勇文译张波 State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China National Key Laboratory of Asic

This paper describes the successful fabrication of 4H-sic junction barrier Schottky （JBS） rectifiers with a linearly graded field limiting ring （LG-FLR）. Linearly variable ring spacings for the FLR termination are applied to improve the blocking voltage by reducing the peak surface electric field at the edge termination region, which acts like a variable lateral doping profile resulting in a gradual field distribution. The experimental results demonstrate a breakdown voltage of 5 kV at the reverse leakage current density of 2 mA/cm2 （about 80% of the theoretical value）. Detailed numerical simulations show that the proposed termination structure provides a uniform electric field profile compared to the conventional FLR termi- nation, which is responsible for 45% improvement in the reverse blocking voltage despite a 3.7% longer total termination length.

关键词： 4H-sic junction barrier Schottky rectifier linearly graded field limiting ring breakdown voltage

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改性纳米sic粉体强化灰铸铁耐磨性能的研究

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铸造 2007年第1期56卷 68-70页

作者：李建卫陈美玲高宏华东理工大学上海200237 大连交通大学辽宁大连116028

在生产条件下采用冲入铸造法制备了改性纳米sic粉体强化灰铸铁材料。研究了不同sic粉体含量灰铸铁的显微组织和力学性能,以及在油润滑条件下的耐磨性能。研究结果表明,经改性纳米sic粉体强化处理后的灰铸铁组织明显细化,力学性能和耐磨... 详细信息

在生产条件下采用冲入铸造法制备了改性纳米sic粉体强化灰铸铁材料。研究了不同sic粉体含量灰铸铁的显微组织和力学性能,以及在油润滑条件下的耐磨性能。研究结果表明,经改性纳米sic粉体强化处理后的灰铸铁组织明显细化,力学性能和耐磨性能明显提高。当纳米sic粉体含量为0.1%时,强化材料的组织和性能最优,抗拉强度提高了22.7%,耐磨损性能提高了20%～78%,强化后灰铸铁耐磨损性能的提高是sic硬质点和石墨润滑协同作用的结果。

关键词：改性纳米sic粉体灰铸铁微观组织耐磨性能

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sic粉末制备技术及其烧结助剂的研究进展

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硅酸盐通报 2014年第9期33卷 2280-2284页

作者：胡继林胡传跃刘鑫田修营湖南人文科技学院化学与材料科学系娄底417000 湖南大学材料科学与工程学院长沙410082

碳化硅(sic)陶瓷由于具有高温强度高、高温抗氧化能力强、热导率高、化学稳定性好等一系列优异性能,在机械、化工、能源和军工等领域得到广泛应用。本文综述了sic粉末的各种制备技术的最新研究进展以及烧结助剂的应用现状,阐述了各种方... 详细信息

碳化硅(sic)陶瓷由于具有高温强度高、高温抗氧化能力强、热导率高、化学稳定性好等一系列优异性能,在机械、化工、能源和军工等领域得到广泛应用。本文综述了sic粉末的各种制备技术的最新研究进展以及烧结助剂的应用现状,阐述了各种方法的特点、基本原理及研究进展,并对几类烧结助剂体系进行了比较。最后展望了各类制备技术今后的研究方向,指出了AlN-Re2O3体系添加剂的优势所在。

关键词： sic 粉末烧结助剂进展

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Research on Vibration Cutting Performance of Particle Reinforced Metallic Matrix Composites sic_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 70-71页

作者： ZHAO Bo 1,2, LIU chuan-shao 2, ZHU Xun-sheng 1, XU Ke-wei 1 (1. Institute of Mechanical Engineering, Shanghai Jiaotong U niversity, Shanghai 200030, China 2. Department of Mechanical Engineering, Jiaozuo Institute of Technology, Hena n 454000, China)

The cutting performance of particle reinforced meta ll ic matrix composites (PRMMCs) sic p/Al in ultrasonic vibration cutting and comm on cutting with carbide tools and PCD tools was experimentally researched in the paper. The changing rules of chip shape, deformation coefficient, shear angle a nd surface residual stress were presented by ultrasonic vibration cutting. Resul ts show: when adopting common cutting, spiral chip with smaller curl radius will be obtained. The chip with zigzag contour is short and thick. There are lots of sheet cracking both on the face of the chip and on the machined surface. That i s to say, the cutting process of metallic matrix composites(MMCs) is not all lik e the cutting process of plastic material. It is akin to the breaking process of brittle material. By comparison, when adopting ultrasonic cutting, because tool contacts with workpiece intermittently in high frequency, deformation of chip i s small, loose spiral chip with larger curl radius is long and thin. The phenome non is just similar to vibration cutting of plastic material. But the chip still belongs to plastic or semi-plastic segmental chip due to the structure charact eristics of the material itself. Furthermore, the tangential residual compressio n stress of vibration cutting is larger than that of common cutting, axial resid ual stress has a relation to the feed rate and residual stress does not changes obviously with cutting depth and they are in the same order of magnitude on the whole. According to the test result analyzing, the following conclusions are put forward: 1) The extruding deformation is serious in common cutting PRMMCs, defo rmation of it’s chip is larger, and the chip with lesser curl radius is short. Whereas, the deformation of chip in vibration cutting PRMMCs is lesser, the curl radius is bigger, and the loose chips are obtained at every turn. 2) The cuttin g deformation coefficient of chip in vibration cutting is lesser than that in co mmon cutting, h

关键词： PRMMCs ultrasonic vibration cutting chip deform ation chip shape

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