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Chinese Journal of Aeronautics 2021年第6期34卷 90-99页

作者： Min LI Minghui LIU Oltmann RIEMER Fangzeng SONG Binghai LYU Intelligent Manufacturing Institute Hunan University of Science and TechnologyXiangtan 411201China Department of Manufacturing Technologies Leibniz Institute for Materials EngineeringBremen 28359Germany Faculty of Production Engineering University of BremenBremen 28359Germany

Based on the special physical–chemical characteristics of optical crystal in the field of aeronautics,a new anhydrous based shear-thickening polishing(ASTP)method has been proposed to restrain deliquescence and to improve physical properties for KDP *** ultraprecision polishing of KDP crystal is completed by ASTP.A kind of anhydrous based thickening polishing slurry(ATPS)was proposed in our work,and high-performance rheological properties were determined to achieve the ASTP of KDP crystal.A material removal model of ASTP in KDP machining is established,followed by the verification experiment of the prediction *** maximum error of the predictive model is only 9.8%,which proves the validity of the material removal model for KDP *** polishing experiments were carried out on the polishing platform developed by *** results show that the new polishing method can polish20 mm×20 mm×5 mm KDP crystal and obtain a super-smooth surface with a surface roughness of 1.37 nm and high shape *** surface accuracy of polished KDP crystal reaches up to0.68 k(RMS).The experimental results show that the ASTP is a potential ultra-precision machining method for KDP crystal.

关键词： Crystals KDP Polishing shear thickening Surface Ultra-precision machining

Signatures of shear thinning-thickening transition in steady shear flows of dense non-Brownian yield stress systems

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Science China Chemistry 2015年第6期58卷 1013-1020页

作者： Wen Zheng Yu Shi Ning Xu CAS Key Laboratory of Soft Matter Chemistry Hefei National Laboratory for Physical Sciences at the Microscale Department of Physics University of Science and Technology of China

Steady shear flows of dense athermal systems composed of soft disks are investigated via non-equilibrium molecular dynamics simulations, from which we sort out links among the structure, dynamics, and shear rheology. The systems at rest are jammed packings of frictionless disks with a nonzero yield stress. Driven by low shear rates, the flows shear thin due to the presence of the nonzero yield stress, but transit to shear thickening above a crossover shear rate γc - At γc, we observe the strongest struc- tural anisotropy in the pair distribution function, which serves as the structural signature of the shear thinning-thickening tran- sition. We also observe dynamical signatures associated with the transition： At γc , scaling behaviors of both the mean squared displacement and relaxation time undergo apparent changes. By performing a simple energy analysis, we reveal an underlying condition for the shear thickening to occur： d（lnTg）/d（Inγ）〉 2 with Tg the kinetic temperature. This condition is confirmed by simulations.

关键词： shear thickening shear thinning structural anisotropy dynamics kinetic temperature

Rheological behavior of semi-solid TiB_2 reinforced Al composite

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Transactions of Nonferrous Metals Society of China 2015年第9期25卷 2827-2832页

作者： S.THADELA B.MANDAL P.DAS H.ROY A.K.LOHAR S.K.SAMANTA Near Net Shape Manufacturing Technology Group CSIR-Central Mechanical Engineering Research Institute NDT & Metallurgy Group CSIR-Central Mechanical Engineering Research Institute

The rheological behavior of the semi-solid Ti B2 reinforced Al-Mg alloy composite slurry was investigated,which is required for the mould filling simulations during the semi-solid *** B2 reinforced in-situ Al-Mg alloy composite samples were remelted and subsequently brought to the semi-solid temperature regime within the heating chamber of a Searle type *** order to understand the rheological behavior of composites,three different types of experiment were carried out,namely,steady state test,continuous cooling test and isothermal *** from that,the thixotropic nature of the slurry was confirmed from the obtained hysteresis loops during the *** results indicate that when isothermally held,the composite slurry exhibits pseudo-plasticity and shows shear-thinning behavior up to the shear rate of 1300 s^-1,and at higher shear rates（1300 s^-1）,it shows a shear thickening tendency,which is probably due to the agglomeration of non-deformable nano-Ti B2 *** pseudo-plastic behavior of the slurry was also estimated employing intermittent step changes of shear rate（shear jump test）.

关键词： rheology shear thinning in-situ nano-Ti B2 thixotropy shear thickening

SELF-ASSEMBLING AMPHIPHILIC POLYELECTROLYTES AND THEIR NANOSTRUCTURES

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Chinese Journal of Polymer Science 2000年第4期18卷 323-336页

作者： Yotaro Morishima Department of Macromolecular Science Graduate School of Science Osaka University Toyonaka Osaka 560-0043 Japan

The self-assembling behavior of random copolymers of sodium 2-(acrylamido)-2-methylpropanesulfonate (AMPS)and hydrophobic comonomers possessing dodecyl groups linked by various spacer bonds was discussed with a focus on theeffect of the spacer. The characterization of association behavior of such polymers in water using quasielastic light scattering,capillary electrophoresis, NMR relaxation, various fluorescence, and viscoelastic methods was described. These copolymersform a variety of self-assembled nanostructures depending on the type of the spacer. Random copolymers of AMPS and N-dodecylmethacrylamide show a strong preference for intrapolymer self-association even in concentrated aqueous solutionsforming single-macromolecular self-assemblies (unimolecular micelles). In contrast, random copolymers of AMPS anddodecyl methacrylate are prone to undergo interpolymer associations yielding multipolymer micelles. In random copolymersof AMPS and a methacrylate substituted a nonionic surfactant (HO(CH_2CH_2O)_(25)C_(12)H_(25)) (C_(12)E_(25)), dodecyl groups are muchless restricted by the polymer backbone because they are linked via a long, flexible hydrophilic spacer. Thus, the polymer-bound C_(12)E_(25) surfactant moieties form micelles similar to those formed by discrete surfactants, but they are bridged bypolymer chains forming a network structure.

关键词： Self-assemblies Hydrophobically-modified polyelectrolytes Nanostructures Hydrophobic association Unimolecular micelles Multipolymer micelles Transient network Viscoelasticity shear thickening shear thinning

Non-linear Viscoelastic Rheological Properties of PCC/PEG Suspensions

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Chinese Journal of Chemical Physics 2009年第1期22卷 46-50页

作者： Hai-lin Yang Jian-ming Ruan Jian-peng Zou Qiu-mei Wu Zhong-cheng Zhou Yuan-yan Xie State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

The shear thinning and shear thickening rheological properties of PCC/PEG suspension were investigated with the increase of oscillatory amplitude stress at different constant frequencies. The results show that the complex viscosity was initially independent of stress amplitude and obvious shear thinning occurred, then dramatic shear thickening took place after reaching the minimum viscosity. Typically, in a constant frequency of 5 rad/s, the elastic modulus, viscous modulus, and tanδ （δ is the out-of-phase angle） vs. the stress amplitude was investigated. It is found that the elastic modulus initially appeared to be independent of stress amplitude and then exhibited a rapid decrease, but the viscous modulus was independent of amplitude stress at lower amplitude stress. After reaching the minimum value the viscous modulus showed a rapid increase. On the other hand, tanδ increased from 0.6 to 92, which indicates that the transition from elastic to viscous had taken place and tanδ showed a steep increase when shear thickening occurred. Lissajous plots are shown for the dissipated energy vs. different maximum stress amplitude in the shear thinning and shear thickening regions. The relationship of dissipated energy vs. maximum stress amplitude was determined, which follows a power law. In the shear thinning region the exponent was 1.91, but it steeply increases to 3.97 in the shear thickening region.

关键词： Precipitated calcium carbonate Suspension shear thickening Dynamic oscillatory shear Rheological response

Viscoelastic properties of monodisperse spherical silica suspension

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Journal of Central South University of Technology 2007年第6期14卷 737-741页

作者：伍秋美阮建明黄伯云周忠诚邹俭鹏 State Key Laboratory of Powder Metallurgy Central South University

The viscoelastic properties of the suspension of monodisperse spherical silica produced by hydrolysis of tetraethoxysilane in alcohol solvent with ammonia as a catalyst in polyethylene glycol （PEG） were studied. The results show that the SiO2/PEG suspension possesses the reversible shear thinning and shear thickening behaviors. In the shear thinning region, the loss modulus （G＂） almost remains unchanged, whereas the storage modulus （G＇） decreases. In the shear thickening region, G＂ and G＇ increase for the formation of the ＂clusters＂. The larger G＂ over G＇ in all the stress studied shows that the system mainly possesses the viscous property, and that the energy dissipated（Ed） is larger than that stored. Ed of this suspension is proportional to the maximum strain （Tmax） rising with the exponent of 1.92 under low shear stress; however, in the shear thickening region, Ed is proportional to γ max rising with the exponent of 5.00.

关键词： viscoelasticity monodisperse silica suspension shear thickening

Improving the Stab-Resistance Performance of Ultra High Molecular Weight Polyethylene Fabric Intercalated with Nano-Silica-Fluid

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Journal of Shanghai Jiaotong university(Science) 2014年第1期19卷 102-109页

作者：顾隽黄献聪李焱王新灵施楣梧郑震 School of Chemistry and Chemical Engineering Shanghai Jiaotong University Quartermaster Institute of General Logistic Department the Chinese People’s Liberation Army

High performance fibers impregnated by shear thickening fluids(STFs) have been recognized as a kind of latent stab-resistant materials. In our work, the rheological properties of various nano-silica particles in diffierent carriers were first investigated, some of which showed the typical characteristic of shear thickening *** then, the effiects of add-on and surface hydrophilicity of silica particles, the type and concentration of the carriers were discussed in detail. It was found that the systems of hydrophilic silica in ethylene glycol, butylenes glycol and polyethylene glycol(PEG) demonstrated shear thickening; moreover, the reversibility of rheological behaviors of hydrophilic silica-PEG300 suspensions indicated energy dissipation existed within a circulation of shear stress. Furthermore, the detail mechanism of STF based nano-silica particles was explored and a process diagram was presented. Finally, the stab-resistance and morphology of cutting edge of ultra high molecular weight polyethylene(UHMWPE) fabric impregnated STF composites were investigated and the results were *** higher silica add-on was benefit to the improvement of the stab resistance of the composites.

关键词： nanoparticle ultra high molecular weight polyethylene(UHMWPE) composite shear thickening stab-resistance