Rheological Properties of Magnetic Field-Assisted Thickening Fluid and High Efficiency Spherical Polishing of ZrO2 Ceramics

Abstract Shear thickening polishing technology using non-Newtonian polishing fluid is a low-cost, low-damage polishing method for the ultra-precision machining of complex curved surfaces. However, the shortcomings of traditional shear thickening polishing fluid in polishing efficiency and fluid viscosity controllability limit its further application., a novel weak magnetic field-assisted shear thickening polishing fluid (WMFA-STPF) containing carbonyl iron particles (CIPs) is presented in this study, which utilizes its weak magnetorheological effect to strengthen the shear thickening phenomenon. The rheological characteristics of the WMFA-STPF samples were investigated. The results show that WMFA-STPF has good fluidity in the low shear rate range and better thickening characteristics in the working shear rate range. In order to verify the high efficiency, high quality and high uniformity polishing ability of the weak magnetic field-assisted shear thickening polishing technology for the spherical surface of zirconia ceramic workpiece, the contrast polishing experiment was designed and finished. The experimental results show that the weak magnetic field-assisted thickening effect can achieve high efficiency and high quality polishing of hard and brittle ceramics. After 75 min polishing, the surface damage was effectively improved and eliminated, the surface quality and uniformity were greatly improved, and the material removal rate reached 7.82 μm/h, increased by 156%.

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Study on Internal Magnetic Field Assisted Finishing Process Using a Magnetic Machining Jig

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.291-292.281 ◽

2005 ◽

Vol 291-292 ◽

pp. 281-286 ◽

Cited By ~ 2

Author(s):

Yan Hua Zou ◽

Takeo Shinmura

Keyword(s):

Magnetic Field ◽

Surface Roughness ◽

Rotational Speed ◽

High Efficiency ◽

Internal Surface ◽

Processing Method ◽

Machining Process ◽

High Quality ◽

Steel Tubes ◽

Finishing Process

This paper examines a new magnetic field assisted machining process using a magnetic machining jig. By using this process, a high efficiency and high quality internal finishing process can be achieved, and it was clarified that it was very effective to finish the internal surface of a thick tube (5~30mm in thickness). In this study, the experiments performed on the SUS304 stainless steel tubes (10mm in thickness) examine the applicability of improving the internal surface roughness and the roundness of inside tube, and it also examine the effects of a rotational speed of the magnetic machining jig. The results showed that this processing method enables improve the internal surface roughness and the roundness of inside tube. It is clarified that the roundness of inside tube is highly dependent on the rotational speed of magnetic machining jig, and the roundness can be improved rapidly at a higher rotational speed with the magnetic machining jig.

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Fabrication and Characterisation of Magnetorheological Shear Thickening Fluids

Frontiers in Materials ◽

10.3389/fmats.2020.595100 ◽

2020 ◽

Vol 7 ◽

Author(s):

Vladimir Sokolovski ◽

Tongfei Tian ◽

Jie Ding ◽

Weihua Li

Keyword(s):

Magnetic Field ◽

Shear Rate ◽

Magnetic Fields ◽

Applied Magnetic Field ◽

Iron Concentration ◽

Shear Thickening ◽

Zero Magnetic Field ◽

Iron Particles ◽

Shear Thickening Fluid ◽

Iron Concentrations

In this article, a magnetorheological shear thickening fluid (MRSTF) was fabricated based on magnetorheological (MR) material and shear thickening fluid (STF). The STF was firstly fabricated as the liquid phase, and carbonyl iron particles were then mixed with the prefabricated STF to synthesise a series of MRSTFs with various iron concentrations. Then, a rheometer was used to measure their viscosities by varying the shear rate under various magnetic fields. Both static and dynamic tests were conducted to study the rheology of MRSTFs under different magnetic fields. The tested results revealed that the MRSTF showed shear thickening under zero magnetic field and MR effect with increasing applied magnetic field. It was also noted that the viscosity of the MRSTFs can be controlled by both shear rate and the applied magnetic field. The concentration of iron particles played an important role in the MRSTFs’ rheological properties. The MRSTFs with higher iron particle concentrations revealed lower shear thickening effects but higher MR effects, which means the MRSTF with higher iron concentration can be treated as an effective MR fluid. Meanwhile, the MRSTF with low iron concentration displays good shear thickening effect under weak magnetic field. To summarise the behavior of MRSTFs with various iron concentrations and under different magnetic fields, three regions were proposed to provide guidelines to design MRSTFs and assist in their applications.

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ELECTRO-MAGNETORHEOLOGICAL FLUIDS DISPERSING ZEOLITE PARTICLES CONTAINING IRON

International Journal of Modern Physics B ◽

10.1142/s0217979202012438 ◽

2002 ◽

Vol 16 (17n18) ◽

pp. 2405-2411 ◽

Cited By ~ 3

Author(s):

A. SHIBAYAMA ◽

T. MIYAZAKI ◽

K. YAMAGUCHI ◽

K. MURAKAMI ◽

T. FUJITA

Keyword(s):

Magnetic Field ◽

Shear Stress ◽

Shear Rate ◽

Electric Field ◽

Electric Fields ◽

Fluid Viscosity ◽

Magnetic Field Direction ◽

Constant Shear ◽

Stress Curve ◽

Constant Shear Rate

Some functional fluids that respond to both magnetic and electric fields have been prepared and their characteristics are described. In this study, an electro-magnetorheological fluid (EMRF) dispersing zeolite particles containing metallic iron by reducing precipitated magnetite has been investigated. When the viscosity is measured by cone plate viscometer and cylindrical viscometer, electric and magnetic fields are applied both between cone and plate or two cylinders. In case of cone plate, the shear stress at constant shear rate increased with the increase of both magnetic field and electric field. On the other hand when the viscosity is measured by cylindrical viscometer, the shear stress at constant shear rate increased with the increase of electric field, however, the increase rate of shear stress by magnetic field is very small. In this case the magnetic field direction is perpendicular to electric field. The EMRF has typical characteristics to respond with magnetic and electric field. The shear stress of EMRF in electric field is stronger than that of magnetic field. Additionally, the inflection and peak point in the shear rate-shear stress curve are appeared and the behaviors of the clusters in the electric field are observed. The experimental results suggested that the fluid viscosity (shear stress/shear rate) is affected by the arrangement of clusters parallel or perpendicular to the direction of the EMRF flow.

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Discontinuous shear thickening in concentrated suspensions

Philosophical Transactions of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rsta.2018.0211 ◽

2019 ◽

Vol 377 (2143) ◽

pp. 20180211 ◽

Cited By ~ 3

Author(s):

Georges Bossis ◽

Olga Volkova ◽

Yan Grasselli ◽

Oumar Gueye

Keyword(s):

Magnetic Field ◽

Shear Rate ◽

Applied Stress ◽

Volume Fraction ◽

Shear Thickening ◽

Solid Particles ◽

Concentrated Suspensions ◽

Stick Slip ◽

Frictional Contacts ◽

Jamming Transition

The flow of concentrated suspensions of solid particles can be suddenly blocked by the formation of a percolated network of frictional contacts above a critical value of the applied stress. Suspensions of magnetic particles coated with a superplastifier molecule were shown to produce a strong jamming transition. We find that, for these suspensions with an abrupt discontinuous shear thickening, a model using the divergence of the viscosity at a volume fraction that depends on the applied stress does not well describe the observed behaviour both below and above the critical stress. At a constant applied stress above the critical one, we have a stick–slip behaviour of the shear rate whose period can be predicted and scaled as the square root of the relaxation time of the frictional contacts. The application of a small magnetic field allows us to continuously decrease the critical shear rate, and it appears that the yield stress induced by the magnetic field does not contribute to the jamming transition. Finally, it is shown that this jamming transition also appears in the extrusion of a suspension through a die, but with a much slower dynamics than in the case of stress imposed on a rotational geometry. This article is part of the theme issue ‘Heterogeneous materials: metastable and non-ergodic internal structures’.

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Rheology of Magnetorheological Shear Thickening Fluids

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.32.161 ◽

2008 ◽

Vol 32 ◽

pp. 161-164

Author(s):

Wei Hua Li ◽

Xian Zhou Zhang

Keyword(s):

Magnetic Field ◽

Shear Rate ◽

Dynamic Properties ◽

Fluid Dynamic ◽

Shear Thickening ◽

Complex Viscosity ◽

Functional Material ◽

Shear Thickening Fluid ◽

Shear Thickening Fluids ◽

Critical Dynamic

This paper presents fabrication and characterizing of a new functional material, magnetorheological shear thickening fluid (MRSTF), by mixing micron-sized magnetizable particles with nano-sized silica particle based shear thickening fluid. Dynamic properties of the MRSTF were characterized by using a parallel-plate rheometer. The effects of steady-state shear rate and magnetic field on MRSTF rheological properties were addressed. The suspension shows an abrupt increase in complex viscosity beyond a critical dynamic shear rate and a magnetic field controllable characteristic, as well as reversible.

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An Underwater Image Enhancement Algorithm Based on Generative Adversarial Network and Natural Image Quality Evaluation Index

Journal of Marine Science and Engineering ◽

10.3390/jmse9070691 ◽

2021 ◽

Vol 9 (7) ◽

pp. 691

Author(s):

Kai Hu ◽

Yanwen Zhang ◽

Chenghang Weng ◽

Pengsheng Wang ◽

Zhiliang Deng ◽

...

Keyword(s):

Image Quality ◽

Image Enhancement ◽

Quality Evaluation ◽

High Efficiency ◽

Natural Image ◽

High Quality ◽

Generative Adversarial Network ◽

Image Quality Evaluation ◽

Adversarial Network ◽

Underwater Image

When underwater vehicles work, underwater images are often absorbed by light and scattered and diffused by floating objects, which leads to the degradation of underwater images. The generative adversarial network (GAN) is widely used in underwater image enhancement tasks because it can complete image-style conversions with high efficiency and high quality. Although the GAN converts low-quality underwater images into high-quality underwater images (truth images), the dataset of truth images also affects high-quality underwater images. However, an underwater truth image lacks underwater image enhancement, which leads to a poor effect of the generated image. Thus, this paper proposes to add the natural image quality evaluation (NIQE) index to the GAN to provide generated images with higher contrast and make them more in line with the perception of the human eye, and at the same time, grant generated images a better effect than the truth images set by the existing dataset. In this paper, several groups of experiments are compared, and through the subjective evaluation and objective evaluation indicators, it is verified that the enhanced image of this algorithm is better than the truth image set by the existing dataset.

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