Department of Mechanical engineering

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Assessment of polytetrafluoroethylene composites for deep groove ball bearing applications through free run and rolling contact fatigue tests
(Springer Nature, 2025-03) Belgamwar, Sachin U.
Polytetrafluoroethylene (PTFE) is widely used in tribological applications. However, its usage in the ball-bearing application has not been explored. The present study investigates the usage of PTFE composites for deep groove ball (DGB) bearings. Initially, a ball-on-disc experiment is conducted to analyze the interaction between pure PTFE, 40% bronze-filled, 25% glass fiber-filled PTFE composites, and Si3N4 balls by determining the coefficient of friction (COF) and specific wear rate. Then, the reliability of the fabricated DGB is checked through free run and rolling contact fatigue (RCF) tests using a 6-channel DAQ system (OR35-INST). In the free run test, a rotor supported on fabricated polymer bearing sets is rotated up to two million cycles under minimal load conditions. Its vibrational signals and RPM are continuously monitored through an accelerometer and tachometer. After a subsequent number of cycles, the dynamic characteristics of the shaft are recorded using the DAQ system and eddy probes. Finally, an RCF test is conducted to check the load-bearing capacity of the bearing. The bearing is subjected to a 36 N to 108 N (in step of 36 N) load, and the vibration signals are recorded.
Atomistic analysis of the effect of cholesterol on cancerous membrane protein system: unfolding and associated resistance stresses under strain
(Taylor & Francis, 2023-05) Rao, Venkatesh K.P.; Belgamwar, Sachin U.
The low-cholesterol cancerous environment can affect the biophysical behaviour of transmembrane proteins. It is difficult to experiment and measure the dynamics of membrane protein systems when cholesterol concentration is decreasing. In this work, atomistic approach is adopted to investigate the transmembrane protein behaviour during lipid-bilayer separation under strain at different cholesterol concentrations. Finding shows that the decreasing cholesterol across membrane protein system leads to an increase in area-per-lipid and average tilt angle by 6.4% and 62.6%, respectively with decreased order parameter. This observation indicates that the decreased cholesterol concentration in a cancerous environment hinders the bonding and compactness of membrane protein system. Stretching and unfolding of protein were observed during bilayer separation and the resistance stresses decreased by 68.01% for decreasing cholesterol. The cholesterol molecules observed to be bonded with proteins. The investigation revealed that the cholesterol is an important constituent of membrane that impedes the diffusion and resist the detachment of protein at high concentration. Thereby, the transmembrane proteins can retain end terminals positions across the membrane and resist functional failure. This study showed that decreased cholesterol concentration causes significant changes in the biophysical behaviour of the membrane protein system that could trigger the mechanosensitivity of transmembrane proteins under mechanical perturbation.
Atomistic approach to analyse transportation of water nanodroplet through a vibrating nanochannel: scope in bio-NEMS applications
(Taylor & Francis, 2022-03) Belgamwar, Sachin U.; Rao, Venkatesh K.P.
Vibrating nanochannels are gaining interest in the fields of bio nano electromechanical systems (bio-NEMS) owing to their acoustic streaming ability (as a tail of nano-swimmers) and drug transportation mechanism. However, it is challenging to articulate such a mechanism experimentally. In this paper, molecular dynamic simulations are carried out to study the effect of the wall vibrations on the forced transportation of a water nanodroplet through a vibrating nanochannel. Here, the motion of water molecules was governed by modified Lennard–Jones (LJ) potential with an initial hydrophobic solid–liquid interface between the walls of nanochannel and water molecules. The density distribution of water molecules was spread towards the nanochannel walls for high vibration (2 (Å) amplitude and 60 GHz frequencies). The average resistance force increased 95.2% for high configuration wall vibrations, showing an increase of 13.96 pN, compared to 7.15 pN for low configuration wall vibrations (0.5 (Å) amplitude and 15 GHz frequency). This work may have significant implications for the application in the fields such as targeted drug delivery, enhanced oil recovery, nanofluidics and inkjet printing.
Bio-hydrogel for Prolonged Controlled Gastro-retentive Drug Dispenser
(IEEE, 2019) Belgamwar, Sachin U.; Roy, Aniruddha
A carbohydrate based polyacrylamide (Paam) modified with guar gum (GG) bio-hydrogel was developed for triggered, controlled gastro-retentive drug dispenser (GRDD) application. Temperature was applied as external stimuli and acidic medium (pH4) was used to release the drug from gel network. The release phenomenon was observed until 60 hours to understand the suitability for prolonged gastro retentive drug dispensing vehicle. The cytotoxicity was assessed by XTT assay with MCF-7 cell line.
A brief manifestation of anti-bacterial nanofiller reinforced coatings against the microbial growth based novel engineering problems
(Elsevier, 2021) Rathore, Jitendra S.; Belgamwar, Sachin U.
An anti-bacterial material coating can help to break the spread of bacteria and viruses via metallic surfaces of biomedical devices, communication devices, food packages, research laboratories and public infrastructures like shopping malls, transports, toilets, etc. In addition, anti-bacterial material coatings owing to adequate tribomechanical and anti-corrosion properties can also help to resolve a major engineering problem of biofouling on marine installations and watercrafts’ surfaces. In recent times, the use of anti-bacterial nanocomposites coatings is emerging rapidly for various engineering applications. Here, metal matrix nanocomposites (MMNCs) are acquiring a significant role in the upcoming field of anti-bacterial material applications owing to high tribo-mechanical and anti-corrosion properties. The bio-responsive mechanism of MMNC coatings to perform anti-bacterial activities can protect the surfaces in biological environments. The nanofillers in the metal matrix plays a key role during anti-bacterial activities to kill the microbials. The composition of nanofillers can be inorganic, organic and hybrid, including advance nano tropes (i.e., allotropes of carbon and BNNT), which can be reinforced in metal matrix. This review study is addressing a problem of bacterial colonization on the surfaces that causing microbial growth based novel engineering problems and suggesting a facile and low-cost solution through an anti-bacterial MMNC coating.
A brief overview of magnetic metal - carbon nanocomposites
(IAEA, 2022) Belgamwar, Sachin U.
Metal–carbon nanomaterials and nanocomposites are advanced materials that can fulfill modern technologies challenges. In magnetic metal-carbon nanocomposites, the carbon allotropes and metals can interchange as nanofiller and binding matrix. One of the primary concerns with magnetic materials is their structural, thermal, and chemical stability. The composition, temperature, and fabrication method of metal-carbon nanomaterials are the significant factors that can influence their performance. The carbon allotropes such as graphene, CNT, and fullerene can be nanofillers for a metallic magnetic matrix to improve their overall performance. In addition, the magnetic monometallic (Fe, Co, Ni) and bimetallic (Fe–Co, Fe–Ni, Fe–Cu, Co–Cu, and Co-Ni alloys) nanofillers with carbon matrix can also be a combination for metal-carbon nanocomposites. Among these combinations, the carbon allotropes reinforcement in the metal matrix attracts researchers due to its low-cost, facile, and industrially scalability with excellent tribo-mechanical strength, high thermo-electrical properties, and adequate corrosion resistance. These materials are used in applications such as hydrogen fuel cells, microelectronic, bio-medical devices and implants, solid lubricants, catalysts, etc. This review article discusses the fabrication method, reinforcement patterns, compositions, magnetic properties of metal carbon nanocomposites, and future applications
Characterization of quenched MD simulated porous carbon electrodes for supercapacitors
(Elsevier, 2023) Belgamwar, Sachin U.
Energy storage devices are playing a significant role in reducing the harmful effects of global warming. Automobile manufacturers are already shifting towards electric vehicles (EVs) in order to curb vehicular pollution. One of the significant drawbacks of the current EV batteries lies in their power density which limits their application. Supercapacitors are a category of energy storage devices that keep excellent specific power capacity and can be used in a hybrid setup with Li-ion batteries in order to make EVs with longer life and rapid acceleration. Electrode porosity in supercapacitors performs a major role in defining their energy and power density. This work explores the quenched molecular dynamics (QMD) simulations followed by thorough characterization for understanding the bimodal pore size distribution (combination of micro- & mesopores) of a porous electrode structure for maintaining a high energy and power density. We performed simulations at various quench rates on porous carbon structures ranging from 600 K/ps to 5 K/ps. Once the porous structures obtained room temperature (300 K), we characterized it for its pore sizes that allow ions to move in and out of the pores during charging and discharging, respectively. The interconnected channeling method has been developed to identify the channel throats and their lengths for different cases of quench rates. Direct output of this study will help experimentalists in fabricating tunable porosity in order to achieve high energy density while maintaining a relatively good power density of supercapacitors.
A close-packed sphere model for characterising porous networks in atomistic simulations and its application in energy storage and conversion
(Elsevier, 2024-05) Belgamwar, Sachin U.; Mishra, Radha Raman; Roy, Tribeni
Hierarchical (micro, meso & macro) porosity in materials plays a crucial role in influencing the movement of ions which governs the energy and power density during energy storage and conversion. The extant available methods to characterise porosity across scales (nano to meso to macro) lacks rigour and accuracy. Having accurate assessment of the porosity in materials can unlock new designs of electrodes for energy efficient energy storage and conversion devices such as batteries, supercapacitors and fuel cells. Through this work, we report the systematic development of a method to fully characterise the carbon porous networks using a molecular dynamics simulation testbed. Our work entails modelling and simulation of porous carbon structures using quenched molecular dynamics (QMD) simulations using Gaussian Approximation potential (GAP) and benchmarking the results with prior literature. This modelling technique can reliably be used for quantitative characterisation of the interconnectivity in porous structures to study ionic movements and charge transfer mechanisms. A new parameter, namely nearest neighbour search (NNS) coefficient was introduced to quantify homogeneity and networking in the porous structures. NNS coefficient increased from 1.62 to 1.92 with decrease of the annealing temperature from 8000 K to 4000 K in carbon. The procedure outlined was although tested on porous carbon networks, but adaptable to study any other material system at multi-length scales.
Co-deposited Zn-Cu/Gr nanocomposite: Corrosion behaviour and in-vitro cytotoxicity assessment
(Taylor & Francis, 2021-04) Belgamwar, Sachin U.; Rathore, Jitendra S.
Zn-Cu alloys have been considered as potential candidates for bioimplant applications due to their moderate corrosion rate and admirable mechanical properties with non-toxic nature to the human body. However, with the incorporation of advanced reinforcements, such as carbon allotropes, the properties and applicability of a Zn-Cu alloy matrix can be further enhanced. In this research, graphene (Gr) nanoplatelets reinforced Zn-Cu/Gr nanocomposites were synthesised through a modified electro-codeposition method with different concentrations of Gr (25, 50 and 100 mg L−1) in the electrolyte bath. The prepared powder samples were compacted and sintered to form pellets. The pellets were tested for mechanical and in-vitro corrosion. The obtained micro-hardness, compressive yield strength (CYS) and ultimate compressive strength (UCS) of Zn-Cu/Gr (100 mg L−1) nanocomposite are 151 HV, 340 MPs and 362 MPa with increments of 84.1%, 118% and 70.7% compared to pure Zn-Cu alloy, respectively. The reduced wear rates and friction coefficients of Zn-Cu/Gr nanocomposites are attributed to crystallite size refinement and Gr content. The electrochemical corrosion rate is reduced by 66.6% from 33 × 10−3 mm year−1 for pure Zn-Cu alloy to 11 × 10−3 mm year−1 for Zn-Cu/Gr (100 mg L−1) nanocomposites, owing to Gr barrier protection. The in-vitro cytotoxicity assessment reveals that the prepared Zn-Cu/Gr nanocomposite is non-toxic for Gr concentration up to 50 mg L−1 in the electrolyte bath. The results show that a non-toxic Zn-Cu/Gr nanocomposite with outstanding tribo-mechanical and anti-corrosion properties can be synthesised by the proposed method.
Copper-philic carbon nanotubes
(AIP, 2016-04) Belgamwar, Sachin U.
Carbon nanotube is having poor wet-ability with copper metal. Wet-ability of carbon nanotube was improved by exposing and creating more active sites on the surface of carbon nanotube. Carbon nanotubes were subjected to the prolong ultrasonication treatment of 20×103 Hz and 500W, which helped in disentanglement of carbon nanotube agglomerates and in breaking the weak bonds like pentagonal or heptagonal structure on the surface and on the CNT cap. Disentanglement of the carbon nanotube, resulted in exposing the defective sites on the surface and breaking of weak bonds, which assisted in creating the new defects on the surface. This process results in generates more active sites on the surface and it helps in improving the wet-ability of the carbon nanotube in copper.
Critical review of reinforcement effect in peek tribology and its usage in biomedical, coating and bearing applications
(Taylor & Francis, 2025-01) Belgamwar, Sachin U.
Polyetheretherketone (PEEK) is an ultra-high-performance polymer renowned for its excellent wear resistance, making it widely used in tribological applications. However, its high coefficient of friction (COF) can detract from its performance. Reinforcing appropriate filler materials can significantly enhance its tribological properties, making it suitable for biomedical, coatings, and bearing applications. The review’s focus is to provide a detailed understanding of the role of reinforcement in affecting the PEEK tribology, covering different forms of reinforcement from fiber to nanofiller in single or hybrid forms. Moreover, the article develops into the testing conditions that can influence its performance, which include material modification, environmental conditions, lubrication state and testing parameters like load, velocity, etc. Further, an in-depth discussion is provided about the role of reinforcement in PEEK usage in biomedical, bearing and coating applications. This article’s effort provides the researchers with scientific knowledge of the reinforcement role in PEEK tribology and major application usage. Further, it offers different areas where there is scope for improvement.
Cupronickel composites: An overview of recent progress and applications
(CRC Press, 2023) Rathore, Jitendra S.; Belgamwar, Sachin U.
This study presents an overview of the various types of composites and their fabrication methods. The study then presents a summary discussion on the fabrication of various cupronickel composites using electrodeposition method and powder metallurgy method. Cupronickel composites are fabricated by adding reinforcing material into the cupronickel alloy matrix, which has led to a significant interest due to their superior hardness, wear resistance, tensile strength, macrofouling resistance, corrosion resistance anti-bacterial properties. Due to these properties, cupronickel composites are employed in various engineering applications such as condenser tubes, cooling circuits, heat exchangers, microelectronics, and condensers. Based on the critical assessment of the literature, existing challenges with possible solutions and future research opportunities were discussed.
Designing porous electrode structures for supercapacitors using quenched MD simulations
(Elsevier, 2022) Mishra, Radha Raman; Belgamwar, Sachin U.; Roy, Tribeni
Recently, supercapacitors with hierarchical porous structured electrodes are gaining a lot of research interest due to their unique qualities such as high power, durability and eco-friendly nature. In this study, porous structured electrodes were generated using quenched molecular dynamics (QMD) simulations, that can provide high energy density by virtue of high porosity. Here, three different quench rates (16, 8 and 4 K/ps) were applied on liquid carbon system to generate different porous structures. It was observed that at 4000 K, the carbon atoms become disorderly bonded and arranges themselves in an ordered hexagonal ring sheets after the completion of quenching process at 300 K. The porous carbon structures were visualized by contour surface mesh. The pore size distribution showed an increase of 62% on decreasing the quench rate from 16 K/ps to 4 K/ps. These light-weight porous carbon structures may also be tested for mechanical and electrical performances, which can have future implications as electrodes for supercapacitor.
Developing Al@GNPs composite coating for pool boiling applications by combining mechanical milling, screen printing and sintering methods
(Taylor & Francis, 2022-01) Belgamwar, Sachin U.
Due to ever growing ‘demand of the energy’ and for the capability to remove large quantities of heat from the heating surface, pool boiling heat transfer becomes the main attraction for research in search of finding the efficient means for transferring heat. Following this trend, the present study also investigated the pool boiling performance of refrigerants, mainly, pure refrigerant (R-134a) and natural refrigerant (R-600a), on the plain aluminium and two graphene nanoplatelets (GNPs) reinforced aluminium matrix composite (Al@GNPs) coated aluminium heating surface with different thickness (50 ± 5 µm and 125 ± 6 µm), which were synthesised by the help of a three-step technique involving mechanical milling, screen printing and sintering process on the plane aluminium surface. The test is conducted at a saturation temperature of 10°C and heat fluxes ranging from 8.28 kW/m2 to 75.61 kW/m2. Test results of R-134a and R-600a were compared. It is observed that thicker Al@GNPs composite coated surface showed better HTC but with reduced ‘onset of nucleate boiling’ (ONB) wall superheat than the plain Al surface.
Developing sustainable Zn-MWCNTs composite coatings using electrochemical co-deposition method: Tribological and surface wetting behavior
(Taylor & Francis, 2022-02) Belgamwar, Sachin U.
Carbon nanotube (CNT) nanofillers are a part of carbon allotrope family materials with numerous and effective features. Multiple CNTs nested one another is a low-cost and scalable category of CNTs, known as multi-walled CNTs (MWCNTs), which are well-stablised for their excellent mechanical, electrical and thermal properties. In this present work, MWCNTs nanofiller embedded Zn matrix (Zn-MWCNTs) composite coatings were fabricated by adding the different concentrations of MWCNTs (0.5, 0.1 and 0.2 g/L) in the acidic electrolyte bath using electrochemical co-deposition route with uniform embedment. The prepared composite coatings were characterised using advanced characterisation techniques (XRD, FESEM and EDS) for their obtained surface morphology and microstructures. All Zn-MWCNTs composite coatings exhibited enhanced tribo-mechanical performance compared to pure Zn coatings. Zn-MWCNT (0.2 g/L) composite coating exhibited the highest average microhardness value of 119 HV and minimum wear rate of 12.5 × 10−3 mm3N−1m−1 among all the prepared composite coatings, which attributed to the synergistic effect of microstructural refinement and superior mechanical properties of MWCNTs. Surface wetting studies reveal that MWCNTs play an important role in increasing hydrophobicity in terms of contact angle, which increased by 1.93 times for Zn-MWCNT (0.2 g/L) composite coating. The present work may be helpful for facile fabrication of low-cost biocidal Zn-MWCNTs nanocomposite coating.
Development and characterization of Cu-Gr composite coatings by electro-co-deposition technique
(Elsevier, 2020) Rathore, Jitendra S.; Belgamwar, Sachin U.
Graphene nanoplatelets (Gr) are considered as promising reinforcing elements in the composite coatings owing to its exceptional mechanical, electrochemical, electrical, and thermal properties. In the present work, Cu-Gr composite coatings were deposited on stainless steel substrate from the electrolyte bath containing different concentrations of Gr using the electro-co-deposition technique. The microstructure and phases of the Cu-Gr composite coating were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy dispersive x-ray spectroscopy (EDS). Microhardness tester was employed to calculate the microhardness. The experimental results show that the surface morphology and microstructure of the Cu-Gr composite coatings are significantly affected by the reinforcement of Gr. The microhardness of the Cu-Gr (0.2 g/L) composite coating is enhanced by 21.42% compared to the pure Cu coating.
Development of Non-Destructive Dynamic Characterization Technique for MMCs: Predictions of Mechanical Properties for Al@Al2O3 Composites
(MDPI, 2023-07) Belgamwar, Sachin U.; Rao, Venkatesh K.P.
In the past several decades, many destructive and non-destructive testing techniques have been developed to evaluate the characteristics of metal matrix composites (MMCs). This research aims to calculate the mechanical properties of the Al@Al2O3 composites by varying alumina nanoparticles (Al2O3 NPs) content using a non-invasive, position sensing detector (PSD) unit-based optical method. The composite was prepared by a powder metallurgy technique, and its characterization was conducted using SEM and XRD to understand its surface morphology and microstructure. The natural frequency and Young’s modulus of the composite were estimated experimentally. Young’s modulus was calculated using this natural frequency. The proposed study shows that Young’s modulus of the composite increases with an increase in Al2O3 NPs content in the composition, irrespective of the testing method. Along with this, natural frequency also increases with the increase in the Al2O3 NPs content. Evaluated properties were compared with the numerical modeling using COMSOL Multiphysics. The experimental and numerical results are equivalent and within the margin of error. This study illustrates the development of an experimental approach for evaluating the mechanical properties of a composite material. This experimental approach can be used whenever sample dimension and space are constrained to evaluate the mechanical behavior of nanomaterials and nanocomposites.
Effect of current on the characteristics of CuNi-G nanocomposite coatings developed by DC, PC and PRC electrodeposition
(Springer, 2021-08) Rathore, Jitendra S.; Belgamwar, Sachin U.
Copper–nickel (CuNi) and graphene nanoplatelet-reinforced CuNi (CuNi-G) nanocomposite coatings were prepared on the surface of stainless-steel substrates in a citrate bath using direct current (DC), pulse current (PC), and pulse reverse current (PRC) electrodeposition techniques. The effect of various electrodeposition currents on the morphology, composition, contact angle, microstructure, microhardness, and wear performance of the coatings were studied. Substantial changes in the surface morphology and microstructure of CuNi-G nanocomposite coatings were observed. The results show that the incorporation of G significantly enhanced the microhardness and wear resistance of electrodeposited coatings. PC and PRC electrodeposited CuNi-G nanocomposite coatings show higher microhardness and wear resistance than DC electrodeposited coatings because of smaller crystallite size, higher content of G, and lower surface roughness.
Effect of GNPs Concentration on the Pool Boiling Performance of R-134a on Cu-GNPs Nanocomposite Coatings Prepared by a Two-Step Electrodeposition Method
(Springer, 2021-06) Belgamwar, Sachin U.
Graphene nanoplatelets (GNPs) have been widely used as an effective reinforcing element in composite coatings owing to its intrinsic ultrahigh thermal and mechanical properties. This study aims to investigate the role of GNPs concentration on pool boiling performance of R-134a on Cu matrix nanocomposite coatings. Cu-GNPs nanocomposite coatings were synthesized on a plain Cu sample via a two-step electrodeposition method with different concentrations of GNPs (100 mg·L−1, 200 mg·L−1, 300 mg·L−1 and 400 mg·L−1) in the plating bath. The impacts of GNPs concentration on morphology, composition, thickness, roughness and porosity of the composite coatings were investigated. The Cu-GNP nanocomposite coating prepared at 400 mg·L−1 of GNPs concentration in the plating bath exhibited maximum BHT coefficient ratio (hER) of 2.73 than that of the plain Cu sample. It is revealed that the addition of GNPs increased the surface roughness, porosity and density of nucleation site of heating surface, which in turn improved the boiling performance.
Effect of Graphene Nanoplatelets Addition on the Mechanical, Tribological and Corrosion Properties of Cu–Ni/Gr Nanocomposite Coatings by Electro-co-deposition Method
(Springer, 2019-09) Rathore, Jitendra S.; Belgamwar, Sachin U.
Nowadays, corrosion of metals is a major problem faced by marine, chemical and automobile industries. Therefore, several researchers are taking efforts to develop composite coatings reinforced with nanoscale materials for high corrosion resistance. In the present work, graphene nanoplatelets (Gr) are incorporated with Cu–Ni matrix to fabricate Cu–Ni/Gr nanocomposite coatings by electro-co-deposition method. Also, the influence of the various concentrations of graphene nanoplatelets in the plating bath on the surface morphology, elemental composition, microstructure, crystallite size, lattice strain, microhardness, average friction coefficient, wear loss and corrosion resistance of these coatings have been studied. The study shows that the mechanical, tribological and corrosion properties of the coatings are enhanced with graphene nanoplatelets incorporation in Cu–Ni matrix. The measured microhardness for Cu–Ni/Gr (400 mg/L) nanocomposite coating increases by 44.17% compared to pure Cu–Ni coating. Also, immersion study indicates that the incorporation of graphene nanoplatelets stabilizes the corrosion potential and enhances the corrosion resistance.