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周克崧,邓春明,刘敏
《中国工程科学》 2009年 第11卷 第10期 页码 48-54
以WC涂层在飞机起落架的应用作为研究背景,对300 M超高强钢基体上电镀硬铬和超音速火焰喷涂WC-17Co和WC-10Co4Cr涂层的疲劳及与结果表明,有WC涂层300 M钢的疲劳寿命与无涂层300 M钢的疲劳极限和过载下的疲劳寿命相当,WC涂层对300 M钢的疲劳寿命不会产生不良影响;而电镀硬铬使300 M钢的疲劳极限降低120 MPa,疲劳寿命则降低疲劳失效分析表明, WC涂层中的疲劳裂纹在界面上发生偏斜,转向沿界面扩展,因此对基体的疲劳寿命没有影响;而电镀硬铬中的的疲劳裂纹扩展到基体表面,显著降低基体的疲劳寿命。;而WC涂层仅略有失重,相应地Al—Ni—Bronze合金的失重仅为与电镀硬铬层磨损失重的1/50~1/100。WC涂层与Al—Ni—Bronze合金的磨损机理主要为磨粒磨损;电镀硬铬与Al—Ni—Bronze合金的磨损机理主要为黏着磨损。
Jinhua Zhang, Yuanbin She
《化学科学与工程前沿(英文)》 2020年 第14卷 第6期 页码 1052-1064 doi: 10.1007/s11705-019-1908-y
关键词: density functional theory methanol direct methanol fuel cells WC(0001)-supported Pd monolayer decomposition mechanism
Jagdeep SINGH,Rajiv Kumar SHARMA
《机械工程前沿(英文)》 2016年 第11卷 第4期 页码 374-387 doi: 10.1007/s11465-016-0388-8
Electrical discharge machining (EDM) is a well-known nontraditional manufacturing process to machine the difficult-to-machine (DTM) materials which have unique hardness properties. Researchers have successfully performed hybridization to improve this process by incorporating powders into the EDM process known as powder-mixed EDM process. This process drastically improves process efficiency by increasing material removal rate, micro-hardness, as well as reducing the tool wear rate and surface roughness. EDM also has some input parameters, including pulse-on time, dielectric levels and its type, current setting, flushing pressure, and so on, which have a significant effect on EDM performance. However, despite their positive influence, investigating the effects of these parameters on environmental conditions is necessary. Most studies demonstrate the use of kerosene oil as dielectric fluid. Nevertheless, in this work, the authors highlight the findings with respect to three different dielectric fluids, including kerosene oil, EDM oil, and distilled water using one-variable-at-a-time approach for machining as well as environmental aspects. The hazard and operability analysis is employed to identify the inherent safety factors associated with powder-mixed EDM of WC-Co.
关键词: WC hazard and operability analysis (HAZOP) discharging aerosol concentration dielectrics powders
Kamal JANGRA, Sandeep GROVER, Aman AGGARWAL
《机械工程前沿(英文)》 2012年 第7卷 第3期 页码 288-299 doi: 10.1007/s11465-012-0333-4
Wire electrical discharge machining (WEDM) is a well known process for generating intricate and complex geometries in hard metal alloys and metal matrix composites with high precision. In present work, intricate machining of WC-5.3%Co composite on WEDM has been reported. Taguchi’s design of experiment has been utilised to investigate the process parameters for four machining characteristics namely material removal rate, surface roughness, angular error and radial overcut. In order to optimize the four machining characteristics simultaneously, grey relational analysis (GRA) coupled with entropy measurement method has been employed. Through GRA, grey relational grade has been computed as a performance index for predicting the optimal parameters setting for multi machining characteristics. Using Analysis of Variance (ANOVA) on grey relational grade, significant parameters affecting the multi-machining characteristics has been determined. Confirmatory results prove the potential of present approach.
关键词: tungsten carbide composite wire electrical discharge machining (WEDM) Taguchi method grey relational analysis (GRA) entropy measurement method
蒸汽压力和超疏水纳米复合涂层对微电子器件可靠性的影响 Article
樊学军,陈良彪,汪正平,Hsing-Wei Chu,张国旗
《工程(英文)》 2015年 第1卷 第3期 页码 384-390 doi: 10.15302/J-ENG-2015034
王飚,王宇栋,李慧玲,张自华
《中国工程科学》 2002年 第4卷 第9期 页码 75-80
在碳钢母材上,用氧乙炔焰喷焊镍包铝合金粉末制取预涂层,喷焊50% Al2O3+50% Ni的复合粉末制取过渡层,用等离子喷焊Al2O3 - MxOy复合粉末制取最终涂层。在质量分数为60%的硫酸与磷矿粉组成的混合介质(质量比为6∶4)中运转,所获得涂层的抗腐抗磨能力为18-8不锈钢的7.46倍,为德产316L不锈钢的4.06倍。
关键词: Al2O3-MxOy 涂层 等离子 抗腐蚀 抗磨损
Wide gap active brazing of ceramic-to-metal-joints for high temperature applications
K. Bobzin,L. Zhao,N. Kopp,S. Samadian Anavar
《机械工程前沿(英文)》 2014年 第9卷 第1期 页码 71-74 doi: 10.1007/s11465-014-0291-0
Applications like solid oxide fuel cells and sensors increasingly demand the possibility to braze ceramics to metals with a good resistance to high temperatures and oxidative atmospheres. Commonly used silver based active filler metals cannot fulfill these requirements, if application temperatures higher than 600°C occur. Au and Pd based active fillers are too expensive for many fields of use. As one possible solution nickel based active fillers were developed. Due to the high brazing temperatures and the low ductility of nickel based filler metals, the modification of standard nickel based filler metals were necessary to meet the requirements of above mentioned applications. To reduce thermally induced stresses wide brazing gaps and the addition of Al2O3 and WC particles to the filler metal were applied. In this study, the microstructure of the brazed joints and the thermo-chemical reactions between filler metal, active elements and WC particles were analyzed to understand the mechanism of the so called wide gap active brazing process. With regard to the behavior in typical application oxidation and thermal cycle tests were conducted as well as tensile tests.
关键词: wide gap active brazing nickel filler metals high temperature application WC Al2O3
通过 B 位Ta置换对 AB O4型EuNbO4的热学和力学性质进行优化 Article
陈琳, 冯晶
《工程(英文)》 2020年 第6卷 第2期 页码 177-184 doi: 10.1016/j.eng.2019.12.006
铁弹性的ABO4型RETaO4陶瓷和RENbO4陶瓷(RE表示稀土)是具有潜在应用价值的热障涂层(TBC)材料,
钠超离子导体型固体电解质的改性及其在钠离子电池中的应用 Article
张强强, 周权, 陆雅翔, 邵元骏, 戚钰若, 戚兴国, 钟贵明, 杨勇, 陈立泉, 胡勇胜
《工程(英文)》 2022年 第8卷 第1期 页码 170-180 doi: 10.1016/j.eng.2021.04.028
固体电解质的低离子电导率及固体电解质与固态电极之间较差的界面可靠性是阻碍固态钠电池(SSSB)应用的两大紧迫挑战。本文采用简单的两步固相法合成了名义成分为Na3+2xZr2‒xMgxSi2PO12 的钠(Na)超离子导体(NASICON)型固体电解质,其中在25 ℃时Na3.3Zr1.85Mg0.15Si2PO12(x=0.15, NZSP-Mg0.15)表现出了3.54 mS∙cm‒1的最高离子电导率。通过深入研究,本文证实晶界成分在决定NASICON总离子电导率中起着至关重要的作用。此外,由于文献中缺乏关于NASICON是否能够提供足够的阳极电化学稳定性来实现高压固态钠电池的研究,我们首先使用了高压Na3(VOPO4)2F (NVOPF)正极来验证其与优化后的NZSP-Mg0.15固体电解质之间的兼容性。通过比较不同配置(低压阴极与高压阴极、液态电解质与固体电解质)电池的电化学性能,以及对循环后的NZSP-Mg0.15进行X射线光电子能谱(XPS)评估,结果表明,NASICON固体电解质在高电压下不够稳定,这证明了研究NASICON固体电解质和高压阴极之间界面的重要性。此外,通过将NZSP-Mg0.15 NASICON 粉末涂在聚乙烯(PE)隔膜(PE@NASICON)上,形成了2.42 A∙h 的碳|PE@NASICON|NaNi2/9Cu1/9Fe1/3Mn1/3O2 非水系钠离子电池,其具有出色的循环性能,在2000 周循环后容量保持率为88%,从而证明涂有NASICON型固体电解质的隔膜具有高可靠性。
标题 作者 时间 类型 操作
Mechanism of methanol decomposition on the Pd/WC(0001) surface unveiled by first-principles calculations
Jinhua Zhang, Yuanbin She
期刊论文
different dielectrics on environmentally conscious powder-mixed EDM of difficult-to-machine material (WC-Co
Jagdeep SINGH,Rajiv Kumar SHARMA
期刊论文
Optimization of multi machining characteristics in WEDM of WC-5.3%Co composite using integrated approach
Kamal JANGRA, Sandeep GROVER, Aman AGGARWAL
期刊论文
Wide gap active brazing of ceramic-to-metal-joints for high temperature applications
K. Bobzin,L. Zhao,N. Kopp,S. Samadian Anavar
期刊论文
祝京旭:药物涂层模式的转变-从溶剂到干粉涂层(2019年5月25日)
2021年04月22日
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