Faculty Publications
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Publications by NITK Faculty
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Item Mechanical properties and sliding wear behavior of jatropha seed cake waste/epoxy composites(Springer Japan, 2015) Shivamurty, B.; Murthy, K.; Joseph, P.C.; Rishi, K.; Bhat, K.U.; Anandhan, S.Jatropha seed cake particulate (JSCP)-reinforced epoxy composites were prepared by open mold resin casting method. The influence of JSCP on mechanical and dry sliding wear properties of epoxy was experimentally investigated as per the ASTM standards. Dry sliding wear test was conducted for these composites at a constant sliding distance of 500 m with different sliding velocities and applied loads by a pin-on-disc wear test machine. The results revealed that incorporation of JSCP decreased the specific wear rate and coefficient of friction while improving the mechanical properties. The composite reinforced with 40 wt% of JSCP exhibited better mechanical properties and wear behavior compared to the neat epoxy and other compositions of JSCP/epoxy composites. The results of this study indicate that jatropha seed cake powder can be used as biosolid lubricant filler for epoxy. © 2014, Springer Japan.Item Thermal and cost analysis of float and various tinted double window glass configurations on heat gain into buildings of hot & dry climatic zone in India(International Information and Engineering Technology Association info@iieta.org, 2018) Gorantla, G.; Saboor, S.; Setty, A.B.T.P.R.Glass window enclosures for buildings consume a lot of energy for affording thermal and visual comfort. Reducing solar radiation in summer and increase in winter through different double window glasses for making energy efficient building design is the theme of this paper. Therefore this work measures the spectral characteristics of four glasses namely grey, green, bronze and clear glasses in entire solar spectrum region from 300nm to 2500nm at normal angle of incidence by using Shimadzu UV 3600 spectrophotometer based on ASTM standards. To find the solar optical properties a MATLAB code was used which is based on British standards. To find the solar radiation transmission from different double window glass configurations and cost analysis from eight coordinal directions at peak summer and winter day were selected as per Indian standards with a MATLAB code to hot and dry climatic zone of Jodhpur (26.300N, 73.020E). From these results it is shows that in south direction all double glass windows are gaining less heat in summer and more heat in winter season when compared to other orientations. It is found that south orientation C1(Greyglasswindow-Airgap10mm-Greenglasswindow) and C12(Clearglasswindow-Airgap10mm-Bronzeglasswindow) configuration windows are gaining minimum and maximum heat in summer and winter respectively when compared to other configuration windows. Among all windows C1 configuration window is saving more cost annually. © 2018 International Information and Engineering Technology Association. All rights reserved.Item Thermal and energy saving analysis by using tinted double window glass combinations for heat gain in buildings(Regional Energy Resources Information Center (RERIC) rericjournal@ait.ac.th, 2018) Gorantla, K.; Saboor, S.; Babu, A.; Ranga, P.; Setty, T.Buildings consume large amount of energy to accommodate thermal and visual comforts, in which glass windows play an important role as we used as building envelope. Universally clear glass is used as chief building envelope for buildings. As clear glass is having more transmission property it permits more radiation and day light into the buildings which creates uneasy feeling to the occupants. This paper presents the experimental measurement of spectral characteristics of three tinted glasses which include transmission and reflection in entire solar spectrum wavelength region from 300nm to 2500nm as per ASTM standards by using UV 3600 Shimadzu spectrophotometer. These measured spectral characteristics were used to compute solar optical properties as per British standard by using MATLAB code. To find the total solar radiation through double tinted window glass combinations GC1 to GC6 place as building envelopes of New Delhi climatic zone by using MATLAB code and to find the monthly solar radiation passing into the building which is helpful to calculate the cost energy saving annually for cooling and heating loads. From the results GC6 combination windows are saving cost i.e. 61.16 (US Dollars/year) in south, 60.54 (US Dollars/year) in south east and 59.23 (US Dollars/year) in south west orientations annually than other combination windows.Item Mechanical Properties of Chemical Treated Woven Banana/Polyvinyl Alcohol Composites(ICE Publishing, 2019) Gunge, A.; Kivade, S.B.; Nagamadhu, M.Present work investigates the effect of chemical treatment on mechanical properties of plain woven banana fabrics (PWBF) reinforced to polyvinyl alcohol (PVA) bio-degradable matrix composite. Woven banana fabrics are chemically treated with different percentages of concentration (0.5, 1, 2, 3 and 4%) for 4 hours at room temperature. The banana fabrics and PVA are used in the ratio of 55% and 45% weight fraction respectively. Composites are prepared using hand-layup method. The samples are tested according to different ASTM standard for tensile, flexural and impact.The results are exhibited that tensile, flexural and impact properties were found to increase with potassium permanganate (KMnO4) treatment. The 1% potassium permanganate treated fabrics shows very good mechanical properties compared to untreated, 0.5, 2, 3 and 4% treated fabrics, 1% treated fabrics gives 68.07% increment in the tensile strength of the composite compared to the untreated fabrics composite. The scanning electron microscopy (SEM) also reveals 1% treated has the better interfacial bonding between fabrics and matrix. This contributes to improvement in the mechanical properties of the composite. © 2019 ICE Publishing: All rights reserved.Item Improved fatigue crack growth resistance by retrogression and re-aging heat treatment in 7010 aluminum alloy(Blackwell Publishing Ltd, 2019) Nandana, M.S.; Bhat K, U.K.; Manjunatha, C.M.Aircraft grade 7010 aluminum alloy was heat treated to two different conditions: (1) standard peak aging (T6) and (2) retrogression and re-aging (RRA). The microstructures of these alloys were characterized by using transmission electron microscope. Fatigue crack growth rate (FCGR) tests were conducted using standard compact tension specimens, following ASTM standards. Tests were conducted at various stress ratios, R ranging from 0.1 to 0.7. The RRA-treated alloy was observed to contain coarsened ?? (MgZn2) precipitates with higher inter-particle spacing when compared with T6-treated alloy. The grain boundary precipitates (GBPs) were also coarsened and discontinuous in RRA-treated alloy as compared with continuous GBPs in T6 condition. The FCGR was lower and ?Kth was higher in RRA-treated alloy compared with T6-treated alloy at all the stress ratios investigated. Improved fatigue crack growth resistance in RRA-treated alloy was correlated to the modified microstructure and enhanced crack closure levels. © 2018 Wiley Publishing Ltd.Item Tribo-mechanical and physical characterization of filament wound glass/epoxy composites(Institute of Physics Publishing helen.craven@iop.org, 2019) Biradar, S.; Joladarashi, S.; Kulkarni, S.M.The present research aims to investigate mechanical, physical and tribological properties of filament wound Glass Fibre Reinforced Polymer (GFRP) composite pressure vessel as per respective ASTM standards. Here test coupons prepared from GFRP vessel are subjected to tensile, compression, flexural and impact testing to investigate mechanical properties. The physical properties are studied from density, ignition loss and water absorption tests. The tribological study was carried out using abrasive slurry erosion tester. All tests carried out in this study are as per respective ASTM standard. The results obtained from various mechanical testings are satisfactory and also almost equal in strength with respect to metallic pressure vessels. Particularly from impact testing, the strength of sea water treated sample has considerably increased. Fractography study was conducted on failed samples to study various mode of failure in detail. The physical characterization has elaborated the behavior of filament wound GFRP material under moisture environment which has observed a maximum of 0.5% water absorption rate. As per ignition loss study which reveals about 95%-98% weight of ignition loss is recorded, which indicates perfect fibre to resin ratio and almost nil or least % of void content. The slurry erosion test results are within the expected range and maximum wear of 9.67% is recorded under extreme case. The overall study reveals that the presence of voids, non-uniform distribution of fibre and matrix have an impact on the outcomes of many mechanical properties. From the above study we can conclude that filament wound GFRP pressure vessel can be used in many applications since it is a non-hydrophobic, better wear resistant and several strength parameters have also improved or unaltered under rigorous testing conditions. © 2019 IOP Publishing Ltd.Item Thermal and Flammability Properties of Glass Fabric/MWCNT/Epoxy Multilayered Laminates(Korean Institute of Electrical and Electronic Material Engineers, 2021) Shivamurty, B.; Anandhan, S.; Bhat, K.U.; Thimmappa, B.H.S.Multiwalled Carbon Nano Tube (MWCNT) filled glass fabric reinforced epoxy composites (MWCNT/GEC), and neat GEC were prepared by hand-lay-up followed by hot compression molding method. As per the ASTM standard, specimens were prepared and investigated the influence of the addition of MWCNTs on flammability properties of GEC through the UL-94 vertical flammability test and the limiting oxygen index (LOI) method. The thermal degradation was studied by thermogravimetric analysis (TGA). It was found that the GEC improved upon the thermal stability and fire-retardant properties due to the addition of MWCNTs. It was observed that the 0.3 wt.% MWCNTs-glass fabric reinforced epoxy composite (0.3MWCNT/GEC) exhibits better properties than neat GEC and 0.075 wt.% MWCNT-glass fabric reinforced epoxy composite (0.075MWCNT/GEC) and 0.15 wt.% MWCNT-glass fabric reinforced epoxy composites (0.15MWCNT/GEC). Hence, this material may be suitable for electrical devices and appliances based on the other required properties’ further fulfillment. © 2021, The Korean Institute of Electrical and Electronic Material Engineers.Item Friction and wear study of graphite and bronze filled epoxy matrix composites(Elsevier Ltd, 2022) Patil, N.; Krishna, P.The composite material is made of different materials. It retains the advantages of the original material and reflects combined characteristics of all the constituents. Polymer matrix composites are popular in the recent industrial applications. Friction and wear governs the tribological aspects of polymer composites. This paper revel the experimental study of friction and wears behavior of epoxy composites filled with bronze and graphite fillers as per ASTM standards. Three compositions were studied and it was found that composition ‘A’ has lowest coefficient of friction (0.281) whereas composition ‘C’ has highest coefficient of friction (0.325). The composition ‘A’ has lowest wear rate of 0.5 μm/s and composition ‘C’ showed highest wear rate of 3.25 μm/s. Use of graphite and bronze along with epoxy exhibited formation of lubricating layer and enhanced friction and wear behavior of the composites. © 2021Item Investigation of mechanical properties of luffa fibre reinforced natural rubber composites: Implications of process parameters(Elsevier Editora Ltda, 2024) Gurjar, A.K.; Kulkarni, S.M.; Joladarashi, S.; Doddamani, S.Natural fiber-reinforced composite materials are highly beneficial due to their excellent strength-to-weight ratio, and the compression molding process is frequently used to prepare natural fiber composites. The primary objective of the present work is to optimize the process parameters of the compression molding method to prepare luffa fiber-reinforced natural rubber composite and investigate the influence of process parameters on mechanical properties. Pre-processing parameters, specifically oven-dry temperature and time, processing parameters such as soaking temperature, time, and compression pressure, and post-processing parameters, such as oven-dry temperature and time, were considered to optimize. Natural rubber in its latex phase is utilized as a matrix material, and luffa fiber is used as reinforcement. The Plackett-Burman screening design technique was employed to identify the impact of different processing parameters on the mechanical properties of the luffa fiber-reinforced natural rubber (LNR) composite, and based on Taguchi's design of experiments, several process parameters were utilized to create L27 orthogonal array and the mentioned composites prepared accordingly. The ASTM standard is followed while testing the composite samples to determine their density, shore A hardness, and tensile strength. The density of the composite is unaffected by the process parameters; however, the shore A hardness of the composite is significantly affected. All the processing parameters most significantly impacted the tensile strength of LNR composites. The optimized process parameters for preparing LNR composite are the pre-oven temperature of 65 °C and time of 150min, the soaking temperature of 75 °C and time of 5min, compression pressure of 1.5 MPa, and the post-oven dry temperature of 55 °C and time of 45min. LNR composite can absorb energy due to its rubber matrix, making it useful for high-impact applications. © 2024 The AuthorsItem Analysis of UNS S31603 ferrous joint made by rotary friction welding(Springer, 2024) Senthil Murugan, S.; Girisankar, S.; Devanathan, C.; Kattimani, S.This study delves into the effects of employing low friction pressure and high axial penetration during the fabrication of friction-welded joints using UNS S31603 stainless steel. The experiments were conducted using a continuous-drive rotary friction welding machine. Crucially, the research showcases the feasibility of creating robust welds in the metal, surpassing the strength of the parent metal. The resulting weld interfaces were remarkably narrow and well-defined. The mechanical properties of the welded joints, including tensile strength, yield strength, microhardness, impact toughness, and bending/flexural strength, were meticulously evaluated following ASTM standards. The findings indicate that the welded joints exhibited impressive tensile strength, approximately 803 MPa, and withstood a peak load of 52.0 kN. Additionally, these joints demonstrated a maximum elongation of 15.3% and a yield strength of 714.0 MPa. When subjected to bending conditions, similar joints made of UNS S31603 withstood loads of up to 19.0 kN before experiencing crack propagation. Ductility was observed in the fracture mode within the weld region, characterized by the formation of cup and cone necking, highlighting the joints' ductile behaviour. Furthermore, the joint efficiency was calculated to be over 100%. Utilizing these specific parameters, this method resulted in a maximum axial shortening or material loss of approximately 14 mm. © Indian Academy of Sciences 2024.