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991.
A. Gnanavelbabu Kaliyamoorthy Rajkumar P. Saravanan 《Materials and Manufacturing Processes》2018,33(12):1313-1323
Aluminum metal matrix composites (AMMCs) explicitly show better physical and mechanical properties as compared to aluminum alloys and results in a more preferred material for a wide range of applications. The addition of reinforcements embargo AMMCs employment to industry requirements by increasing order of machining complexity. However, it can be machined with a high order of surface integrity by nonconventional approaches like abrasive water jet machining. Hybrid aluminum alloy composites were reinforced by B4C (5–15?vol%) and solid lubricant hBN (15?vol%) particles and fabricated using a liquid metallurgy route. This research article deals with the experimental investigation on the effect of process parameters such as mesh size, abrasive flow rate, water pressure and work traverse speed of abrasive water jet machining on hybrid AA6061-B4C-hBN composites. Water jet pressure and traverse speed have been proved to be the most significant parameters which influenced the responses like kerf taper angle and surface roughness. Increase in reinforcement particles affects both the kerf taper angle and surface roughness. SEM images of the machined surface show that cutting wear mechanism was largely operating in material removal. 相似文献
992.
Polypyrrole (PPR)–carbon nanotube (CNT) films were prepared by an electrodeposition method, combining PPR electropolymerization and anaphoresis of CNT. PPR polymerization experiments showed advantages of a dopant from the catechol family for the deposition of PPR films at reduced electrode potentials. The method allowed the formation of adherent films on stainless steel substrates. The amphiphilic molecules with steroid-like structures, such as carbenoxolone disodium salt, glycyrrhizic acid, ammonium salt, and sodium taurodeoxycholate, were used for dispersion and charging of CNT. The new dispersing agents showed outstanding dispersion ability. In addition to dispersing properties, electrodeposition experiments revealed film-forming properties of carbenoxolone and ability to form pure carbenoxolone or carbenoxolone–CNT films. The PPR–CNT films formed using carbenoxolone disodium salt, glycyrrhizic acid ammonium salt, and sodium taurodeoxycholate showed diverse microstructural features. The dispersion and deposition mechanisms were discussed. 相似文献
993.
Diversity in Addressing Reaction Mechanisms of Nano‐Thermite Composites with a Layer by Layer Structure 下载免费PDF全文
994.
995.
Uniting Strength and Toughness of Al Matrix Composites with Coordinated Al3Ni and Al3Ti Reinforcements 下载免费PDF全文
Hybrid aluminum composites are fabricated in a novel manner to characteristically induce a layer‐wise aligned distribution of micro‐scale Al3Ni and Al3Ti intermetallic particles that are formed in situ within a ductile Al matrix. The simple and unique Rolling of Randomly Orientated Layer‐wise Materials (RROLM) manufacturing methodology enables microstructural tailoring of the intermetallic reinforcing particles to prescribe enhanced crack tip deflection caused by the complex interaction of local veins of reinforcement particles, in an effort to overshadow the classical loss of toughness in large‐particle reinforced composites. The complimentary reinforcements and their interface with the Al matrix are revealed to have a gradual transition zone that functions to maintain critical cohesion with the particles and the matrix, empowering the superior load transfer capability of the particles, and reducing microvoid penetration into the matrix. In situ three‐point bending observations combined with a local strain field analysis, demonstrate the distinctive crack deflection mechanisms exhibit by the composite. Deviating from the norm, this specialized particle reinforced composite exhibited both strengthening and toughening mechanisms simultaneously, over control samples. The investigated design strategy and model material will assist materials development toward light‐weight, stronger, and tougher particle reinforced Al matrix composites. 相似文献
996.
Effect of High‐Energy Ball Milling on Mechanical Properties of the Mg–Nb Composites Fabricated through Powder Metallurgy Process 下载免费PDF全文
997.
Dendrite‐Free Lithium Deposition via Flexible‐Rigid Coupling Composite Network for LiNi0.5Mn1.5O4/Li Metal Batteries 下载免费PDF全文
Jingchao Chai Bingbing Chen Fang Xian Peng Wang Huiping Du Jianjun Zhang Zhihong Liu Huanrui Zhang Shanmu Dong Xinhong Zhou Guanglei Cui 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(37)
Notorious lithium dendrite causes severe capacity fade and harsh safety issues of lithium metal batteries, which hinder the practical applications of lithium metal electrodes in higher energy rechargeable batteries. Here, a kind of 3D‐cross‐linked composite network is successfully employed as a flexible‐rigid coupling protective layer on a lithium metal electrode. During the plating/stripping process, the composite protective layer would enable uniform distribution of lithium ions in the adjacent regions of the lithium electrode, resulting in a dendrite‐free deposition at a current density of 2 mA cm?2. The LiNi0.5Mn1.5O4‐based lithium metal battery presents an excellent cycling stability at a voltage range of 3.5–5.0 V with the induction of 3D‐cross‐linked composite protective layer. From an industrial field application of view, thin lithium metal electrodes (40 µm, with 4 times excess lithium) can be used in LiNi0.5Mn1.5O4 (with industrially significant loading of 18 mg cm?2 and 2.6 mAh cm?2)‐based lithium metal batteries, which reveals a promising opportunity for practical applicability in high energy lithium metal batteries. 相似文献
998.
High‐energy storage devices are in demand for the rapid development of modern society. Until now, many kinds of energy storage devices, such as lithium‐ion batteries (LIBs), sodium‐ion batteries (NIBs), and so on, have been developed in the past 30 years. However, most of the commercially exploited and studied active electrode materials of these energy storage devices possess a single phase with low reversible capacity or unsatisfied cycle stability. Continuous and extensive research efforts are made to develop alternative materials with a higher specific energy density and long cycle life by element doping or surface modification. A novel strategy of forming composite‐structure electrode materials by introducing structure units has attracted great attention in recent years. Herein, based on previous publications on these composite‐structure materials, some important scientific points focusing on the design of composite‐structure materials for better electrochemical performances reveal the distinction of composite structures based on average and local structure analysis methods, and an understanding of the relationship between these interior composite structures and their electrochemical performances is discussed thoroughly. The lithiation/delithiation mechanism and the remaining challenges and perspectives for composite‐structure electrode materials are also elaborated. 相似文献
999.
为使涤纶织物应用范围更广,更耐磨,本文制备了一种有机硅树脂基纳米硼化钛碳化钛复合涂层,通过正交实验法得到最佳的涂层方案,并尝试将其应用于涤纶织物,以改善涤纶织物的表面结构,进而实现涤纶织物表面优异的耐磨性能.为测试涂层对涤纶织物性能的影响, 采用泰伯式耐磨仪、液滴形状分析仪、电子织物强力机、扫描电子显微镜(SEM)研究了涂层织物的耐磨性能、疏水性能、物理机械性能和磨损织物的表面微观形态.研究表明:当有机硅树脂与无水乙醇质量比为75: 25,含量(质量分数)为93%;超分散剂含量为1.5%;乙醇增稠剂含量为1.5%;纳米硼化钛和碳化钛质量比为2: 1,含量为4%时,所得涂层溶液应用于涤纶织物后会形成一层包覆层,耐磨性能最优.对于涂覆量为15 g/m2的涤纶,拉伸断裂强力由573.92 N提高到620.48 N,顶破强力由652.34 N提高到790.07 N,撕裂强力由9.87 N降低到5.78 N,疏水性能有较大提高,接触角可达到120°以上. 相似文献
1000.