Magneto-rheological abrasive finishing (MAF) of soft material using abrasives

The present work explores the potential of magneto-rheological fluid assisted abrasive finishing (MRF-AF) for obtaining precise surface topography of an in-house developed β-phase Ti-Nb-Ta-Zr (TNTZ) alloy for orthopedic applications. Investigations have been made to study the influence of the concentration of carbonyl iron particles (CIP), rotational speed (Nt), and working gap (Gp) in response to material removal (MR) and surface roughness (Ra) of the finished sample using a design of experimental technique. Further, the corrosion performance of the finished samples has also been analyzed through simulated body fluid (SBF) testing. It has been found that the selected input process parameters significantly influenced the observed MR and Ra values at 95% confidence level. Apart from this, it has been found that Gp and Nt exhibited the maximum contribution in the optimized values of the MR and Ra, respectively. Further, the corrosion analysis of the finished samples specified that the resistance against corrosion is a direct function of the surface finish. The morphological analysis of the corroded morphologies indicated that the rough sites of the implant surface have provided the nuclei for corrosion mechanics that ultimately resulted in the shredding of the appetite layer. Overall results highlighted that the MRF-AF is a potential technique for obtaining nano-scale finishing of the high-strength β-phase Ti-Nb-Ta-Zr alloy.

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Analysis of magneto rheological elastomers for energy harvesting systems

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209350 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 439-446

Author(s):

Gildas Diguet ◽

Gael Sebald ◽

Masami Nakano ◽

Mickaël Lallart ◽

Jean-Yves Cavaillé

Keyword(s):

Magnetic Field ◽

Energy Harvesting ◽

Shear Strain ◽

Magnetic Induction ◽

Magnetic Particles ◽

Homogeneous Magnetic Field ◽

Electrical Signal ◽

Harvesting Systems ◽

Dc Bias ◽

Magneto Rheological

Magneto Rheological Elastomers (MREs) are composite materials based on an elastomer filled by magnetic particles. Anisotropic MRE can be easily manufactured by curing the material under homogeneous magnetic field which creates column of particles. The magnetic and elastic properties are actually coupled making these MREs suitable for energy conversion. From these remarkable properties, an energy harvesting device is considered through the application of a DC bias magnetic induction on two MREs as a metal piece is applying an AC shear strain on them. Such strain therefore changes the permeabilities of the elastomers, hence generating an AC magnetic induction which can be converted into AC electrical signal with the help of a coil. The device is simulated with a Finite Element Method software to examine the effect of the MRE parameters, the DC bias magnetic induction and applied shear strain (amplitude and frequency) on the resulting electrical signal.

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Thickness Estimation Method of a Hard Object Located in a Soft Material using a Grasping Forceps with Sensors for Tumor Detection

IEEJ Transactions on Sensors and Micromachines ◽

10.1541/ieejsmas.136.377 ◽

2016 ◽

Vol 136 (9) ◽

pp. 377-383

Author(s):

Kai Saito ◽

Akihito Nakai ◽

Ken Masamune ◽

Takeyoshi Dohi ◽

Kenta Kuwana

Keyword(s):

Estimation Method ◽

Tumor Detection ◽

Soft Material ◽

Thickness Estimation

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Parametric Study of Damping Characteristics of Magneto-Rheological Damper: Mathematical and Experimental Approach

Pollack Periodica ◽

10.1556/606.2020.15.3.4 ◽

2020 ◽

Vol 15 (3) ◽

pp. 37-48

Author(s):

Zubair Rashid Wani ◽

Manzoor Ahmad Tantray

Keyword(s):

Structural Control ◽

Research Work ◽

Testing Machine ◽

Input Voltage ◽

Damping Coefficient ◽

Control Technique ◽

Damping Force ◽

Active Devices ◽

Active Structural Control ◽

Magneto Rheological

The present research work is a part of a project was a semi-active structural control technique using magneto-rheological damper has to be performed. Magneto-rheological dampers are an innovative class of semi-active devices that mesh well with the demands and constraints of seismic applications; this includes having very low power requirements and adaptability. A small stroke magneto-rheological damper was mathematically simulated and experimentally tested. The damper was subjected to periodic excitations of different amplitudes and frequencies at varying voltage. The damper was mathematically modeled using parametric Modified Bouc-Wen model of magneto-rheological damper in MATLAB/SIMULINK and the parameters of the model were set as per the prototype available. The variation of mechanical properties of magneto-rheological damper like damping coefficient and damping force with a change in amplitude, frequency and voltage were experimentally verified on INSTRON 8800 testing machine. It was observed that damping force produced by the damper depended on the frequency as well, in addition to the input voltage and amplitude of the excitation. While the damping coefficient (c) is independent of the frequency of excitation it varies with the amplitude of excitation and input voltage. The variation of the damping coefficient with amplitude and input voltage is linear and quadratic respectively. More ever the mathematical model simulated in MATLAB was in agreement with the experimental results obtained.

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Improve the Micro-hardness of Single Point Incremental Forming Product Using Magnetic Abrasive Finishing

Engineering and Technology Journal ◽

10.30684/etj.v38i8a.906 ◽

2020 ◽

Vol 38 (8A) ◽

pp. 1137-1142

Author(s):

Baqer A. Ahmed ◽

Saad K. Shather ◽

Wisam K. Hamdan

Keyword(s):

Vickers Hardness ◽

Feed Rate ◽

Incremental Forming ◽

Single Point ◽

Single Point Incremental Forming ◽

Step Size ◽

Coil Current ◽

Magnetic Abrasive Finishing ◽

Finishing Process ◽

Abrasive Finishing

In this paper the Magnetic Abrasive Finishing (MAF) was utilized after Single Point Incremental Forming (SPIF) process as a combined finishing process. Firstly, the Single Point Incremental forming was form the truncated cone made from low carbon steel (1008-AISI) based on Z-level tool path then the magnetic abrasive finishing process was applied on the surface of the formed product. Box-Behnken design of experiment in Minitab 17 software was used in this study. The influences of different parameters (feed rate, machining step size, coil current and spindle speed) on change in Micro-Vickers hardness were studied. The maximum and minimum change in Micro-Vickers hardness that achieved from all the experiments were (40.4 and 1.1) respectively. The contribution percent of (feed rate, machining step size, coil current and spindle speed) were (7.1, 18.068, 17.376 and 37.894) % respectively. After MAF process all the micro surface cracks that generated on the workpiece surface was completely removed from the surface.

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MACHINERY OPERATIONAL PROPERTY CONTROL DURING DIAMOND-ABRASIVE FINISHING USING ACTIVE SOTS

Bulletin of Bryansk state technical university ◽

10.30987/1999-8775-2020-9-13-17 ◽

2020 ◽

Vol 2020 (9) ◽

pp. 13-17

Author(s):

Yuriy Ryzhov ◽

Svetlana Abramova

Keyword(s):

Corrosion Inhibitors ◽

Tribological Behavior ◽

Surface Layers ◽

Physical Chemical ◽

Abrasive Finishing ◽

Alloying Additives ◽

Phosphorus Containing ◽

Micro Emulsion ◽

Property Control ◽

Diamond Abrasive

There is carried out a number of experiments with the purpose of analyzing SOTS impact upon both finishing productivity, and physical-chemical state and tribological behavior of surfaces machined, and also a possibility for creation according to the results of the investigations carried out a relatively universal micro-emulsion SOTS based on existing in the Ukraine the line of oils, PAV, corrosion inhibitors, alloying additives etc. As SOTS samples there were used both well-known compouds, for example, Camix, Nope Right (USA), and carbamide having in its structure boron, boron-phosphorus-containing additive, water-solvable phosphate, tributyl phosphate (oil-solvable), concentrate SOTS tribol, having in its structure compounds of boron, nitrogen and phosphorous; ethylic ether of fatty acids; methyl ether of colza oil; Sarkozyl-O having in its structure easily-decomposable chlorine compounds. From the results obtained it is possible to draw a conclusion that during finishing in the environment of water-compatible SOTS an important role in the formation of the properties of the surface worked is played by hydrocarbon components and additives which contribute to the formation of the thinnest surface layers modified with carbon and oxygen.

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