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Rheological Characterization of Vegetable-Oil-based Magnetorheological Finishing Fluid
Available online at www.sciencedirect.com
ScienceDirect Materials Today: Proceedings 18 (2019) 3526–3531
www.materialstoday.com/proceedings
ICMPC-2019
Rheological Characterization of Vegetable-Oil-based Magnetorheological Finishing Fluid Vikas Kumara*, Rajesh Kumara, Harmesh Kumara a
Department of Mechanical Engineering, U.I.E.T. (Panjab University), Chandigarh, 160025, INDIA
Abstract Magnetorheological (MR) finishing fluids are the backbone of MR finishing technology. The rheological behavior of MR finishing fluid helps to attain required abrading force during a finishing operation. The rheological properties of MR finishing fluid changes with the applied magnetic field strength as well as with the fluid composition. Magnetizable iron particles, nonmagnetic abrasive particles and non-magnetic carrier liquid are the main constituents of MR finishing fluid sample. The selection of a carrier liquid is equally important along with other constituents of MR finishing fluid. In the present work, coconut oil, as an eco-friendly carrier liquid, was selected for the preparation of MR finishing fluid. The performance of the developed sample in terms of rheological properties was tested under different magnetic field strengths. The structure of the prepared sample exhibits more strength at the higher magnetic field strengths. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019 Keywords: Magnetorheological finishing fluid; Rheological properties; Magnetic field; Carrier liquid.
1. Introduction Magnetorheological (MR) finishing fluids are based on smart characteristics of Magnetorheological (MR) fluids. MR fluids are composed of micron-sized magnetizable particles which are usually dispersed in a carrier liquid with some additives. In general, MR fluids behave like a Newtonian fluid. MR fluids turn to semi-solid within a fraction of a second under the effect of a magnetic field (so called on-state condition), and this change is reversible. This is
* Corresponding author. Tel.: +919467711006. E-mail address: [email protected] 2214-7853 © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019
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due to the interaction of magnetizable particles which align themselves along magnetic field lines and form a columnar chain structure. The columnar chain structure exhibits resistance to deformation while undergoing shearing under shear mode conditions. This is due to the rise in yield stress of MR fluids during the on-state condition. The yield stress and viscosity both increase primarily with the increase in applied magnetic field strength. Because of these features, MR fluids have potential application in the field of chemical engineering (MR valves), civil engineering (seismic dampers), mechanical engineering (automobile shock absorbers, clutches) and many more other industrial applications. MR fluid devices operates under different modes, viz. shear, squeeze and valve mode [1]. One of the shear mode applications of MR fluids is used in optical finishing. The unique characteristics of MR fluids are utilized successfully in finishing operations. Similar to conventional finishing operations, MR-fluid-based finishing operations are also based on the mechanism of mechanical abrasion but in a more controlled manner. This is because of the involvement of MR fluid technology in finishing operations, which provides selective control of abrading forces that are otherwise difficult to control in conventional finishing operations. Researchers have reported the successful use of MR fluid technology in finishing of optical glasses and extended it to hard metals and alloys. Finishing processes which involve the effective utilization of MR fluid technology include Magnetorheological finishing (MRF) process [2,3,4], Wheel-based MR finishing process [5,6], MR fluid finishing for curved surfaces [7], Magnetorheological abrasive flow finishing (MRAFF) process [8], Rotational- Magnetorheological abrasive flow finishing (R-MRAFF) process [9,10], Magnetorheological jet finishing (MRJF) process [11,12], Ball end magnetorheological finishing (BEMRF) process [13], and Magnetorheological abrasive honing (MRAH) process [14]. In all these processes, the mechanical abrasion of the workpiece surface takes place. This is because the material is removed from the workpiece surface by the selective action of active abrasives particles only or by the combined action of abrasive and magnetic particles that actually act on the workpiece surface during a finishing operation. For use in finishing processes, a suitable quantity of non-magnetic abrasive particles needs to be added in MR fluids, which helps to achieve the desired surface characteristics. The composition of MR fluids consisting of a dispersion of non-magnetic abrasives is termed as “Magnetorheological (MR) finishing fluids”. Non-magnetic abrasives in MR finishing fluid are embedded in between magnetizable particles, which hinders the complete formation of columnar chain structure of magnetizable particles. Because of this, the on-state yield stress of MR fluid decreases up to some extent but still the fluid structure retains enough strength which helps to achieve the desired surface characteristics of the work material. Normally, the rheological behavior of MR finishing fluids depend on the applied magnetic field strength, but it also changes with temperature and composition of MR finishing fluid. The composition of MR finishing fluid used in a finishing process plays an important role in deciding the magnitude of abrading force acting on the workpiece surface at a particular magnetic field. Therefore, it becomes more important to evaluate the rheological behavior of MR finishing fluids in order to obtain the desired outcome in a particular application. Several researchers have synthesized and evaluated MR finishing fluid compositions for their effective use in the particular finishing applications. Jha and Jain [15] have synthesized different MR finishing fluid samples containing varying sizes of abrasive particles and characterized their rheological behavior with a variation in magnetic field strength on an in-house developed magneto-rheometer. They have found that experimental data points fit better with the Herschel Bulkley model with a higher coefficient of determination and at higher magnetic fields, MR finishing fluid samples with bigger abrasives exhibit more shear thinning behavior. Similarly, the magnetorheological data of MR finishing fluid samples synthesized by Sidpara et al. [16] fits better with the Herschel Bulkley model. They concluded that the yield stress increases with the increase in applied magnetic field strength and magnetic particle concentration, while it decreases with the increase in temperature. Sidpara et al. [17] synthesized MR finishing fluid samples by varying the content of its constituents and correlated the rheological behavior of these samples in the finishing of single-crystal silicon. They concluded that the on-state yield stress and viscosity increases with the increase in applied magnetic field strength and percent volume concentration of magnetic particles, while it decreases with the increase in concentration of non-magnetic abrasive particles. They suggested that an optimum level of the yield stress and viscosity is necessary in order to obtain the desired surface finish on a work material. The effect of magnetic particle size on the magnetorheological properties of MR finishing fluid at different magnetic
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field strengths was observed by Saraswathamma et al. [18]. They concluded that MR finishing fluid samples exhibit shear thinning behavior and the on-state yield stress and viscosity increases with the increase in applied magnetic field strength as well as size of magnetic particles. Biodegradability of MR finishing fluids is equally important simultaneously with their use in finishing applications, and it depends mainly upon the carrier medium used in the synthesis of fluid. Silicon oil, mineral oil, hydrocarbon oil, deionized water, etc. are the commonly used carrier liquids. Among these carrier liquids, only deionized water is a biodegradable medium. However, it does not provide better suspension to micron-sized iron particles as well as abrasive particles resulting in their fast sedimentation. Further, in water-based MR finishing fluids, the corrosion of iron particles takes place, which degrades the MR effect and hence the yield stress of the fluid structure. Water-based MR fluids are not much suitable for the finishing of internal surfaces as there is a problem of heat dissipation generated during the finishing process. Water-based MR fluid cannot sustain a high temperature obtained during the finishing operation. To overcome these issues, some special processing needs to be carried out during synthesis, like addition of additives to reduce sedimentation and enhancing thermal stability, particle coating to avoid corrosion and improving MR effect, etc., but it enhances the cost of the synthesized fluid. Keeping in view the above problem and the issue of biodegradability, it is important to find an alternative carrier medium which is eco-friendly and overcomes the above mentioned demerits of deionized water. In the present study, coconut oil, which is a vegetable-based biodegradable oil, is used as a carrier medium. A coconut-oil-based MR finishing fluid sample was prepared and rheological characterization was carried out at different magnetic field strengths in order to know the flow behavior of the fluid sample under respective magnetic field strengths. 2. Materials Coconut oil was used as a carrier liquid in the preparation of MR finishing fluid sample. The commercially available iron particles (325 mesh size, Sigma-Aldrich) and green silicon carbide (SiC) abrasives (SFG LAP-40, Speedfam Co. Ltd.) were used as dispersed phase in the carrier liquid.
Fig. 1. SEM micrographs (a) Fe particles; (b) SiC abrasives.
The scanning electron microscopy (SEM) images of iron particles and SiC abrasives are shown in Fig. 1a and 1b, respectively. The x-ray diffraction (XRD) pattern of iron particles and SiC abrasives are shown in Fig. 2a and 2b, respectively. The MR finishing fluid sample was prepared by mixing 35 vol% iron particles and 10 vol% SiC abrasives in the base carrier liquid (coconut oil). To obtain uniform dispersion of magnetic and non-magnetic particulates in the carrier medium, the mixing of particulates in the carrier medium was carried out for 45 min. with the help of a mechanical stirrer.
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Fig. 2. X-ray diffraction pattern (a) Fe particles; (b) SiC abrasives.
3. Rheological Characterization The magnetorheological characterizations were performed at 25 °C using a modular compact rheometer (MCR-102, Anton Paar, Germany) available at IIT, Ropar (Fig. 3). A magnetorheological device (MRD 180) attached to the modular compact rheometer provides homogeneous magnetic field in a direction perpendicular to the shear flow direction. During rheological testing, an approximately 0.3 ml of the fluid sample was filled in the lower plate cavity that is fixed to the rheometer. The parallel plate geometry (PP/20) was used with a gap of 1 mm. The shear rate was varied from 0.1 to 1000 s−1 during rheological testing. The rheological measurements were carried out at different magnetic field values (0, 0.2, 0.4, 0.6 T) to observe the effect of magnetic field strength on the rheological properties of the fluid sample.
Fig. 3. Anton-Paar modular compact rheometer (MCR-102).
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4. Results and Discussion Fig. 4 shows flow curves (shear stress vs shear rate) of fluid sample at different magnetic field strengths. Fig. 4 reveals that the commencement of fluid flow starts only after a critical shear stress value which is termed as yield stress of the MR finishing fluid sample. This kind of behavior is observed at all the magnetic field strength values.
Fig. 4. Shear stress vs Shear rate of MR finishing fluid sample under various magnetic field strengths.
Fig. 4 shows that the magnitude of shear stress increases with an increase in applied magnetic field strength. This may be due to the reason that the magnetic interaction force between iron particles increases with the increase in magnetic field strength. Under the effect of higher magnetic field strength, the stiffness of MR finishing fluid structure increases due to the strong chain-like structure of iron particles. A higher magnitude of force is required to break such kind of a fluid structure.
Fig. 5. Viscosity vs Shear rate of MR finishing fluid sample under various magnetic field strengths.
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The change in shear viscosity as a function of shear rate at different magnetic field strengths is shown in Fig. 5. It depicts that the viscosity of the MR finishing fluid sample decreases as the shear rate increases. This kind of behavior is observed at each value of applied magnetic field strength, which shows the shear thinning behavior of the fluid sample. 5. Conclusion In this research work, vegetable oil (coconut oil) was used as a carrier liquid for the preparation of MR finishing fluid sample. The performance of fluid sample in terms of rheological properties has been tested under different magnetic field strength values. The prepared sample showed an increase in yield stress with the increase in magnetic field strength, which means that the prepared sample exhibits more rigid structure under higher magnetic field strength. Thus, the ‘vegetable oil’ can be useful as a carrier liquid in the preparation of MR finishing fluid. Acknowledgements The authors express gratitude to UGC, Government of India for providing BSR fellowship; Technical Education Quality Improvement Programme (TEQIP)-III, MHRD, Government of India for providing funds for testing; and Sophisticated Analytical Instrumentation Facility (SAIF), Panjab University, Chandigarh for providing their lab facilities for this research work. References [1] [2] [3] [4] [5] [6] [7] [8] [9]
B.K. Kumbhar, S.R. Patil, S.M. Sawant, Eng Sci Technol: an Int J 18 (2015) 432–438. W. Kordonski, D. Golini, Int J Mod Phys B 13 (1999) 2205–2212. M. Schinhaerl, C. Vogt , A. Geiss, et al., Proc SPIE 7060 (2008) 1–12. C. Miao, J.C. Lambropoulos, S.D. Jacobs, Appl Opt 49 (2010) 1951–1963. W-B. Kim, S-H. Lee, B-K. Min, Trans ASME- J Manuf Sci Eng 126 (2004) 772–778. H.B. Cheng, Y. Yam, Y.T. Wang, J Mater Process Technol 209 (2009) 5254–5261. J. Seok, Y. Kim, K. Jang, et al., Int J Mach Tools Manuf 47 (2007) 2077–2090. S. Jha and V.K. Jain, Int J Mach Tools Manuf 44 (2004) 1019–1029. M. Das, V.K. Jain, P.S. Ghoshdastidar, Proceedings of the ASME 2009 International Manufacturing Science and Engineering Conference (2009) 1–10. [10] M. Das, V.K. Jain, P.S. Ghoshdastidar, Mach Sci Technol 14 (2010) 365–389. [11] W.B. Kim, E. Nam, BK. Min, et al., Int J Precis Eng Manuf 16 (2015) 629–637. [12] W. Kordonski, A. Shorey, J Intell Mater Syst Struct 18 (2007) 1127–1130. [13] A.K. Singh, S. Jha, P.M. Pandey, Int J Mach Tools Manuf 51 (2011) 142–151. [14] A. Sadiq, M.S. Shunmugam, Int J Mach Tools Manuf 49 (2009) 554–560. [15] S. Jha, V.K. Jain, Int J Adv Manuf Technol 42 (2009) 656–668. [16] A. Sidpara, M. Das, V.K. Jain, Mater Manuf Process 24 (2009) 1467–1478. [17] A. Sidpara, V.K. Jain, Mach Sci Technol 18 (2014) 367–385. [18] K. Saraswathamma, S. Jha, P.V. Rao, Mater Manuf Process 30 (2015) 661–668.
ScienceDirect Materials Today: Proceedings 18 (2019) 3526–3531
www.materialstoday.com/proceedings
ICMPC-2019
Rheological Characterization of Vegetable-Oil-based Magnetorheological Finishing Fluid Vikas Kumara*, Rajesh Kumara, Harmesh Kumara a
Department of Mechanical Engineering, U.I.E.T. (Panjab University), Chandigarh, 160025, INDIA
Abstract Magnetorheological (MR) finishing fluids are the backbone of MR finishing technology. The rheological behavior of MR finishing fluid helps to attain required abrading force during a finishing operation. The rheological properties of MR finishing fluid changes with the applied magnetic field strength as well as with the fluid composition. Magnetizable iron particles, nonmagnetic abrasive particles and non-magnetic carrier liquid are the main constituents of MR finishing fluid sample. The selection of a carrier liquid is equally important along with other constituents of MR finishing fluid. In the present work, coconut oil, as an eco-friendly carrier liquid, was selected for the preparation of MR finishing fluid. The performance of the developed sample in terms of rheological properties was tested under different magnetic field strengths. The structure of the prepared sample exhibits more strength at the higher magnetic field strengths. © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019 Keywords: Magnetorheological finishing fluid; Rheological properties; Magnetic field; Carrier liquid.
1. Introduction Magnetorheological (MR) finishing fluids are based on smart characteristics of Magnetorheological (MR) fluids. MR fluids are composed of micron-sized magnetizable particles which are usually dispersed in a carrier liquid with some additives. In general, MR fluids behave like a Newtonian fluid. MR fluids turn to semi-solid within a fraction of a second under the effect of a magnetic field (so called on-state condition), and this change is reversible. This is
* Corresponding author. Tel.: +919467711006. E-mail address: [email protected] 2214-7853 © 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the 9th International Conference of Materials Processing and Characterization, ICMPC-2019
V. Kumar et al./ Materials Today: Proceedings 18 (2019) 3526–3531
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due to the interaction of magnetizable particles which align themselves along magnetic field lines and form a columnar chain structure. The columnar chain structure exhibits resistance to deformation while undergoing shearing under shear mode conditions. This is due to the rise in yield stress of MR fluids during the on-state condition. The yield stress and viscosity both increase primarily with the increase in applied magnetic field strength. Because of these features, MR fluids have potential application in the field of chemical engineering (MR valves), civil engineering (seismic dampers), mechanical engineering (automobile shock absorbers, clutches) and many more other industrial applications. MR fluid devices operates under different modes, viz. shear, squeeze and valve mode [1]. One of the shear mode applications of MR fluids is used in optical finishing. The unique characteristics of MR fluids are utilized successfully in finishing operations. Similar to conventional finishing operations, MR-fluid-based finishing operations are also based on the mechanism of mechanical abrasion but in a more controlled manner. This is because of the involvement of MR fluid technology in finishing operations, which provides selective control of abrading forces that are otherwise difficult to control in conventional finishing operations. Researchers have reported the successful use of MR fluid technology in finishing of optical glasses and extended it to hard metals and alloys. Finishing processes which involve the effective utilization of MR fluid technology include Magnetorheological finishing (MRF) process [2,3,4], Wheel-based MR finishing process [5,6], MR fluid finishing for curved surfaces [7], Magnetorheological abrasive flow finishing (MRAFF) process [8], Rotational- Magnetorheological abrasive flow finishing (R-MRAFF) process [9,10], Magnetorheological jet finishing (MRJF) process [11,12], Ball end magnetorheological finishing (BEMRF) process [13], and Magnetorheological abrasive honing (MRAH) process [14]. In all these processes, the mechanical abrasion of the workpiece surface takes place. This is because the material is removed from the workpiece surface by the selective action of active abrasives particles only or by the combined action of abrasive and magnetic particles that actually act on the workpiece surface during a finishing operation. For use in finishing processes, a suitable quantity of non-magnetic abrasive particles needs to be added in MR fluids, which helps to achieve the desired surface characteristics. The composition of MR fluids consisting of a dispersion of non-magnetic abrasives is termed as “Magnetorheological (MR) finishing fluids”. Non-magnetic abrasives in MR finishing fluid are embedded in between magnetizable particles, which hinders the complete formation of columnar chain structure of magnetizable particles. Because of this, the on-state yield stress of MR fluid decreases up to some extent but still the fluid structure retains enough strength which helps to achieve the desired surface characteristics of the work material. Normally, the rheological behavior of MR finishing fluids depend on the applied magnetic field strength, but it also changes with temperature and composition of MR finishing fluid. The composition of MR finishing fluid used in a finishing process plays an important role in deciding the magnitude of abrading force acting on the workpiece surface at a particular magnetic field. Therefore, it becomes more important to evaluate the rheological behavior of MR finishing fluids in order to obtain the desired outcome in a particular application. Several researchers have synthesized and evaluated MR finishing fluid compositions for their effective use in the particular finishing applications. Jha and Jain [15] have synthesized different MR finishing fluid samples containing varying sizes of abrasive particles and characterized their rheological behavior with a variation in magnetic field strength on an in-house developed magneto-rheometer. They have found that experimental data points fit better with the Herschel Bulkley model with a higher coefficient of determination and at higher magnetic fields, MR finishing fluid samples with bigger abrasives exhibit more shear thinning behavior. Similarly, the magnetorheological data of MR finishing fluid samples synthesized by Sidpara et al. [16] fits better with the Herschel Bulkley model. They concluded that the yield stress increases with the increase in applied magnetic field strength and magnetic particle concentration, while it decreases with the increase in temperature. Sidpara et al. [17] synthesized MR finishing fluid samples by varying the content of its constituents and correlated the rheological behavior of these samples in the finishing of single-crystal silicon. They concluded that the on-state yield stress and viscosity increases with the increase in applied magnetic field strength and percent volume concentration of magnetic particles, while it decreases with the increase in concentration of non-magnetic abrasive particles. They suggested that an optimum level of the yield stress and viscosity is necessary in order to obtain the desired surface finish on a work material. The effect of magnetic particle size on the magnetorheological properties of MR finishing fluid at different magnetic
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field strengths was observed by Saraswathamma et al. [18]. They concluded that MR finishing fluid samples exhibit shear thinning behavior and the on-state yield stress and viscosity increases with the increase in applied magnetic field strength as well as size of magnetic particles. Biodegradability of MR finishing fluids is equally important simultaneously with their use in finishing applications, and it depends mainly upon the carrier medium used in the synthesis of fluid. Silicon oil, mineral oil, hydrocarbon oil, deionized water, etc. are the commonly used carrier liquids. Among these carrier liquids, only deionized water is a biodegradable medium. However, it does not provide better suspension to micron-sized iron particles as well as abrasive particles resulting in their fast sedimentation. Further, in water-based MR finishing fluids, the corrosion of iron particles takes place, which degrades the MR effect and hence the yield stress of the fluid structure. Water-based MR fluids are not much suitable for the finishing of internal surfaces as there is a problem of heat dissipation generated during the finishing process. Water-based MR fluid cannot sustain a high temperature obtained during the finishing operation. To overcome these issues, some special processing needs to be carried out during synthesis, like addition of additives to reduce sedimentation and enhancing thermal stability, particle coating to avoid corrosion and improving MR effect, etc., but it enhances the cost of the synthesized fluid. Keeping in view the above problem and the issue of biodegradability, it is important to find an alternative carrier medium which is eco-friendly and overcomes the above mentioned demerits of deionized water. In the present study, coconut oil, which is a vegetable-based biodegradable oil, is used as a carrier medium. A coconut-oil-based MR finishing fluid sample was prepared and rheological characterization was carried out at different magnetic field strengths in order to know the flow behavior of the fluid sample under respective magnetic field strengths. 2. Materials Coconut oil was used as a carrier liquid in the preparation of MR finishing fluid sample. The commercially available iron particles (325 mesh size, Sigma-Aldrich) and green silicon carbide (SiC) abrasives (SFG LAP-40, Speedfam Co. Ltd.) were used as dispersed phase in the carrier liquid.
Fig. 1. SEM micrographs (a) Fe particles; (b) SiC abrasives.
The scanning electron microscopy (SEM) images of iron particles and SiC abrasives are shown in Fig. 1a and 1b, respectively. The x-ray diffraction (XRD) pattern of iron particles and SiC abrasives are shown in Fig. 2a and 2b, respectively. The MR finishing fluid sample was prepared by mixing 35 vol% iron particles and 10 vol% SiC abrasives in the base carrier liquid (coconut oil). To obtain uniform dispersion of magnetic and non-magnetic particulates in the carrier medium, the mixing of particulates in the carrier medium was carried out for 45 min. with the help of a mechanical stirrer.
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Fig. 2. X-ray diffraction pattern (a) Fe particles; (b) SiC abrasives.
3. Rheological Characterization The magnetorheological characterizations were performed at 25 °C using a modular compact rheometer (MCR-102, Anton Paar, Germany) available at IIT, Ropar (Fig. 3). A magnetorheological device (MRD 180) attached to the modular compact rheometer provides homogeneous magnetic field in a direction perpendicular to the shear flow direction. During rheological testing, an approximately 0.3 ml of the fluid sample was filled in the lower plate cavity that is fixed to the rheometer. The parallel plate geometry (PP/20) was used with a gap of 1 mm. The shear rate was varied from 0.1 to 1000 s−1 during rheological testing. The rheological measurements were carried out at different magnetic field values (0, 0.2, 0.4, 0.6 T) to observe the effect of magnetic field strength on the rheological properties of the fluid sample.
Fig. 3. Anton-Paar modular compact rheometer (MCR-102).
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4. Results and Discussion Fig. 4 shows flow curves (shear stress vs shear rate) of fluid sample at different magnetic field strengths. Fig. 4 reveals that the commencement of fluid flow starts only after a critical shear stress value which is termed as yield stress of the MR finishing fluid sample. This kind of behavior is observed at all the magnetic field strength values.
Fig. 4. Shear stress vs Shear rate of MR finishing fluid sample under various magnetic field strengths.
Fig. 4 shows that the magnitude of shear stress increases with an increase in applied magnetic field strength. This may be due to the reason that the magnetic interaction force between iron particles increases with the increase in magnetic field strength. Under the effect of higher magnetic field strength, the stiffness of MR finishing fluid structure increases due to the strong chain-like structure of iron particles. A higher magnitude of force is required to break such kind of a fluid structure.
Fig. 5. Viscosity vs Shear rate of MR finishing fluid sample under various magnetic field strengths.
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The change in shear viscosity as a function of shear rate at different magnetic field strengths is shown in Fig. 5. It depicts that the viscosity of the MR finishing fluid sample decreases as the shear rate increases. This kind of behavior is observed at each value of applied magnetic field strength, which shows the shear thinning behavior of the fluid sample. 5. Conclusion In this research work, vegetable oil (coconut oil) was used as a carrier liquid for the preparation of MR finishing fluid sample. The performance of fluid sample in terms of rheological properties has been tested under different magnetic field strength values. The prepared sample showed an increase in yield stress with the increase in magnetic field strength, which means that the prepared sample exhibits more rigid structure under higher magnetic field strength. Thus, the ‘vegetable oil’ can be useful as a carrier liquid in the preparation of MR finishing fluid. Acknowledgements The authors express gratitude to UGC, Government of India for providing BSR fellowship; Technical Education Quality Improvement Programme (TEQIP)-III, MHRD, Government of India for providing funds for testing; and Sophisticated Analytical Instrumentation Facility (SAIF), Panjab University, Chandigarh for providing their lab facilities for this research work. References [1] [2] [3] [4] [5] [6] [7] [8] [9]
B.K. Kumbhar, S.R. Patil, S.M. Sawant, Eng Sci Technol: an Int J 18 (2015) 432–438. W. Kordonski, D. Golini, Int J Mod Phys B 13 (1999) 2205–2212. M. Schinhaerl, C. Vogt , A. Geiss, et al., Proc SPIE 7060 (2008) 1–12. C. Miao, J.C. Lambropoulos, S.D. Jacobs, Appl Opt 49 (2010) 1951–1963. W-B. Kim, S-H. Lee, B-K. Min, Trans ASME- J Manuf Sci Eng 126 (2004) 772–778. H.B. Cheng, Y. Yam, Y.T. Wang, J Mater Process Technol 209 (2009) 5254–5261. J. Seok, Y. Kim, K. Jang, et al., Int J Mach Tools Manuf 47 (2007) 2077–2090. S. Jha and V.K. Jain, Int J Mach Tools Manuf 44 (2004) 1019–1029. M. Das, V.K. Jain, P.S. Ghoshdastidar, Proceedings of the ASME 2009 International Manufacturing Science and Engineering Conference (2009) 1–10. [10] M. Das, V.K. Jain, P.S. Ghoshdastidar, Mach Sci Technol 14 (2010) 365–389. [11] W.B. Kim, E. Nam, BK. Min, et al., Int J Precis Eng Manuf 16 (2015) 629–637. [12] W. Kordonski, A. Shorey, J Intell Mater Syst Struct 18 (2007) 1127–1130. [13] A.K. Singh, S. Jha, P.M. Pandey, Int J Mach Tools Manuf 51 (2011) 142–151. [14] A. Sadiq, M.S. Shunmugam, Int J Mach Tools Manuf 49 (2009) 554–560. [15] S. Jha, V.K. Jain, Int J Adv Manuf Technol 42 (2009) 656–668. [16] A. Sidpara, M. Das, V.K. Jain, Mater Manuf Process 24 (2009) 1467–1478. [17] A. Sidpara, V.K. Jain, Mach Sci Technol 18 (2014) 367–385. [18] K. Saraswathamma, S. Jha, P.V. Rao, Mater Manuf Process 30 (2015) 661–668.