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Thermal and tool wear characterization of graphene oxide coated through magnetorheological fluids on cemented carbide tool inserts

Thiyagu M., Karunamoorthy L., Arunkumar N.

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

1043--1055

EN

The proposed work is about the investigation of nano-textured tool insert with magnetor-heological-based graphene coating process. The comparative study on nano-textured car-bide insert with unpolished one for turning duplex stainless steel (S31803/2205) is made by conducting number of experiments with Box–Behnken design using response surface methodology. An array of sensor based on the conductive element of chromel and alumel core integrated through DC magnetron sputtering on the rake surface of the tool insert. The performance of the proposed sensor was evaluated from the obtained thermo-electromotive force on tool chip contact interference and the temperature measurements taken at the contours of multiple points with respect to the tool wear. Results obtained clarify that with the rise in cutting tool temperature leads to the rise in tool wear based on the adhesion and abrasion. It has been found that the graphene coated tool inserts provides high wearable resistances with flank wear of 0.298 mm at 21st pass. The cutting tool temperature is found to spread uniformly with a value of 202 8C for graphene coated inserts for cutting speed of 55 m/min. Microstructural images taken proved that the formation of cementite and carbides with inter metallic compounds (IMCs) produced during the tool chip interface leads to the strengthening of tool tip in reducing the tool-wear. Also the occurrence of ultrafine grain boundaries on the tool tip occurs increasing the formation of covalent bonds in providing the robust resistance against tool wears.

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Experimental verification of the semi-active control concepts for torsional vibrations of the electro-mechanical system using rotary magneto-rheological actuators

Pręgowska A., Konowrocki R., Szolc T.

Vibrations in Physical Systems

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2012

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Vol. 25

329--334

EN

In the paper semi-active control of torsional vibrations of the rotating machine drive system driven by an electric motor is performed by means of rotary actuators with the magneto-rheological fluid. The main purpose of these studies is a minimisation of vibration amplitudes in order to increase the fatigue durability of the most responsible elements, assure possibly precise motion of the driven machine working tool as well as to reduce a generated noise level. For suppression of steady-state torsional vibrations excited by dynamic external torques generated by the motor and by the driven object there are proposed control strategies based on a principle of optimum current damping coefficient values realized by the magneto-rheological fluid. The theoretical control concepts are experimentally verified using the laboratory test rig in the form of drive system co-operating with two asynchronous motors generating properly programmed driving and retarding electromagnetic torques.

3

Neural network modeling of the semi-active magneto-rheological fluid damper

Nabagło T., Pietraszek J.

Czasopismo Techniczne. Mechanika

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2010

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R. 107, z. 2-M

193-201

EN

The paper describes model of a semi-active damper based on Magneto-Rheological Fluid (MRF). This model is constructed in a neural networks (NN) system. Such a solution is used because of nonlinear character of the MRF damper elements. The result of research and calculations exposes ways to solve problems connected with this kind of modeling processes. In the final part of the paper, the authors compare results of the NN model verification process with real MRF damper force to velocity characteristics. The article is a complete description of nonlinear model construction with usage of Radial Basis neural Networks (RBN).

PL

W artykule opisano model tłumika pół-aktywnego opartego na płynach magneto-reologicznych (MR). Model ten zbudowano za pomocą sieci neuronowych. Ze względu na nieliniowy charakter tłumików MR zastosowano modelowanie neuronowe tłumików. Na podstawie badań zaprezentowano sposoby rozwiązywania problemów związanych z tego rodzaju modelowaniem. W końcowej części artykułu autorzy porównują w procesie weryfikacji charakterystykę siły do prędkości wynikłą z symulacji modelu neuronowego z charakterystyką rzeczywistego tłumika MR. Artykuł stanowi kompletny opis konstrukcji modelu tłumika MR za pomocą sieci neuronowej o podstawie radialnej.