NUST Institutions Library Catalogue Search for 'an:"119655"'

Damage modeling of adhesively bonded composite joint under diffrent fiber orientations

By Ammar Azam. . 89 p.

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Damage in composite-metal adhesive joints under low velocity impact conditions /

By Ashraf, Muhammad Umar Bin . . 67p. 30cm.

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Experimental Investigation of Temperature and Cork filler on The Strength of Tubular Adhesive Joint Under Pure Shear Stress /

By Haider, Shamsheer . . 80p. ; 30cm..

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Analysis of Adhesive Joints using Digital Image Correlation (DIC) /

By Farooq, Muhammad Kashif . . 83p. , In this study, the effect of cork particles on the failure behavior of SLJs was investigated experimentally through tensile testing and non-contact digital image correlation (DIC) methods. Cork particles within size range of 125-250 μm were added at 0, 0.25, 0.50, 0.75 and 1.0% wt. in a brittle epoxy. SLJs with and without cork particles were tested under a displacement control condition of 1.3 mm/min and digital images were captured during the deformation in order to analyze the fracture process. VIC 2D 7 software was used to determine the peel and shear strain distributions in the overlapped area of bonded joints. Tensile test and DIC results reveal that cork particles enhance the strength and ductility of adhesive joints. However, the effect of cork particles on ductility is more significant than strength of joint. The visual inspection of the captured images shows cork particles act as crack stopper and slow down the crack propagation along the bondline. 30cm.

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Structural Optimization of Orthopedic Hip Implant Using Different Topology Optimization Algorithms /

By Abdullah, Muhammad . . 76p. , This research investigates the reduction in weight of hip implant by the application of parametric and non-parametric optimization techniques. Orthopaedic hip implants can be made from metals, ceramics, composites, or metallic alloys and are generally solid structures. The stiffness of orthopaedic hip implant is a pertaining problem when implanted in the human body as Hip implant are stiffer than bone material and causes stress shielding. This results in bone weakening which causes osteoporosis. Reduction in mass of femur stem results in stiffness reduction of femur stem. Non-Parametric topology optimization results in 34.9 % mass reduction and parametric optimization based on Central Composite Design technique in Design of Experiments (DoE) uses hole diameters as parameters and performs structural optimization that results in 22% mass reduction. 30cm.

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Finite Element Modelling of Foot Bones In A Patient With Chronic Osteomyelitis /

By JAHANGIR ,SANA . . 104p. ; 30cm..

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Comparison of Machining Simulations of Aerospace Alloy Al6061 using Lagrangian and SPH Techniques /

By NAWAZ ,MUHAMMAD NAUMAN. . 74p. ; 30cm..

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Biomechanical investigation of lower limb injuries in military scenarios: using Finite element modeling approach /

By MUJAHID ,AYESHA . . 57p. ; 30cm..

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Multiscale Modelling Of Adhesive Joints With Nano Fillers /

By Ijaz, Sana . . 71p. , The study examines the strength and durability of single lap joint created using the identical epoxy adhesives (LY-556/AD 22962) that are single lap adhesively joined. As per credible research data available, epoxy adhesives and single lap adhesively bonded joints' failure strengths are influenced by a number of factors, and their strength can be increased using a number of different techniques. Addition of filler material to epoxy is one of the efficient techniques. A flexible natural raw material, cork powder is used to strengthen adhesives and SLJs that are adhesively bonded by acting as a crack-stopping filler. However, with change in concentration of filler, this behavior of cork powder changes. The current work focuses on evaluating differences in the structural characteristics of epoxy-based adhesives and adhesively bonded single lap joints at various temperatures and cork powder concentrations. A series of simulation have been performed for investigation of SLJs strength with LY-556 as epoxy adhesive and Aluminum 5052 as adherend. The adhesively bonded joint is tested at different temperature ranges from 25ºC, 50ºC, 75ºC and 100ºC with the concentration of cork powder ranging from weight percentages of 0.25, 0.5, 0.75 and 1. 30cm.

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Comparison of Ballistic Responses of Different Types High Hardness Perforated Armor Plates Against Armor Piercing Projectiles /

By IBRAHIM ,BILAL. . 81p. ; 30cm..

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Investigation of change in strength of Double Cantilever Beam Adhesive Joints under Mode I failure by addition of Cork Particles /

By AZIZ ,MUBEEN. . 44p. ; 30cm..

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Effect of Hygrothermal Aging on Strength Performance of Cork Powder Reinforced Adhesive /

By Sohail, Zulekha . . 100p. , Adhesives play a crucial role across various industries and applications due to their ability to bond materials together. They are used in numerous ways, ranging from everyday household applications to industrial and specialized fields. Strength is the most critical factor to analyze before using the adhesive. Various techniques have already been developed and many are being developed to predict and improve the strength of adhesive. The addition of cork powder to the structural adhesives could improve the strength of adhesive joints through mechanical interlocking between the cork cells and the molecules of adhesive. However, even with the nanofiller reinforcement, the strength of adhesive joints is significantly affected by environmental parameters like temperature and humidity. The present study investigated the effect of hydrothermal aging on the strength characteristics of cork powder-reinforced adhesive samples. Reinforced adhesive samples were investigated under two different humidity levels of 80% and 100% RH. The cork powder will be added in concentration of 0.25wt.%, 0.5wt.%, 0.75wt.% and 1wt.% to study the reinforcing effects. The result shows that the saturated mass increased with increased in relative humidity that is approximately 0.4% and 0.9% for 80% and 100% RH respectively. The findings show that the ultimate tensile strength is reduced by the addition of cork powder as well as enhancing humidity. Furthermore, the addition of cork powder makes the sample more brittle, so failure strain and tensile toughness undergo decrement. The above finding indicated that hot-wet environment has a negative influence on strength performance of cork powder reinforced adhesive. In future the same study can be performed to know the strength of SLJ and DLJ to know its effect on joints. 30cm.

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Tensile Shear Testing of Double Strap Adhesive joints Using Cork Particles /

By RIAZ ,UMAR. . 50p. ; 30cm..

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Study of High Speed Impact on Composite Armor Structure /

By Muzamil , Muhammad. . 75p. ; 30cm..

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Effect of temperature and filler concentration on the strength of adhesively bonded single lap joint /

By Muqbool ,Yousaira . . 84p. ; 30cm..

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EXPERIMENTAL STUDY OF THE EFFECT OF CORK POWDER INCLUSION ON STRENGTH OF DOUBLE STRAP JOINT AT ELEVATED TEMPERATURES /

By Afshan ,Zar . . 83p. ; 30cm..

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An Investigation of Strength of Adhesives & Single Lap Adhesive Joints at Various Temperatures and Filler Concentrations /

By Chaudary, Kainat Nawaz . . 111p. , The research presents the behavior of the mechanical properties of epoxy adhesives & adhesively bonded single lap joints made using same epoxy adhesives (LY-556 /AD 22962). Research has shown that various factors impact the overall strength of epoxy adhesives & adhesively bonded single lap joints and their strength can be improved through various techniques and processes. One of the effective methods is addition of filler material to adhesive. Cork powder is a versatile natural raw material and being used as a crack stopping filler for enhancing the strength of adhesives & adhesively bonded single lap joints. However, this behavior of cork powder changes with change in filler concentration. Present study is focused on observing the variation in mechanical properties of epoxy adhesive & adhesively bonded single lap joints at different temperatures and different concentrations of cork powder and their effect on mechanical properties of adhesives & adhesively bonded single lap joints. An experimental investigation is conducted to study the strength of LY-556 epoxy adhesives & adhesively bonded single lap joints with Aluminum 5052 adherends at different temperatures and different cork filler concentration. The adhesives & single lap joints are tested under tensile testing at ultimate testing machine. The temperature ranges from 25 degrees, 50 degrees, 75 degrees and 100 degrees and the cork powder concentration for each temperature are 0.25wt.%, 0.5wt.%, 0.75wt.% and 1wt.%. It is observed that for different temperature and for each concentration, the strength of adhesives reflects an increase in toughness with addition of cork powder while overall tensile strength & modulus decreases with increase in cork powder & temperature. Single lap joints shows similar behavior trend so that he highest failure strength is observed at room temperature and at 0.5wt.% cork powder concentration and minimum strength is observed at 100 degrees (close to glass transition temperature) and at 1wt.% concentration. The type of failure is changes from mix mode failure to cohesive failure as temperature and cork powder changes from low to high. 30cm.

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Numerical Analysis of Adhesively Bonded Single Lap Joint /

By Hassan, Muhammad . . 76p. , This research shows the effect of aluminum oxide Al2O3 nanoparticles included in Epocast 50- A1/946 epoxy adhesive at different temperatures in quasi-static tensile loading. The single lap adhesive joint with two different types of material adherends was used: composite fiber reinforced plastic and aluminum 5083 adherends. The effect on peel stress and shear stress was compared by adding Al2O3 nanoparticles into the neat adhesive at 25℃, 50℃, and 75℃ temperatures at four locations of the adhesive region: the top face (interface of aluminum and adhesive), the middle plane of adhesive, the longer edge (along the length of adhesive), the shorter edge (along the width of adhesive). The results show that adding nanoparticles into the neat adhesive improves the strength of the joint at room and elevated temperatures. High peel stress and shear stress were recorded near both edges of the top face (interface). At the top face, the peak peel stress was reduced by 1.3% and increased by 2.7% and 10.7% for 25℃, 50℃, and 75℃ temperatures respectively and the same trend was observed for other locations. At the top face, the peak shear stress decreased by 19.6% and increased by 7.7% and 8.7% for 25℃, 50℃, and 75℃ temperatures respectively and the same trend was observed for other locations. It was noted that adding aluminum oxide nanoparticles made adhesive stiffer at higher temperatures and made it more applicable to bear more force. Moreover, it was also noted that the peak of stress lies near the edges , indicating that the crack will most probably start close to the edges along the length of adhesive and translate towards the center and causes ultimate failure. 30cm.

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Investigating The Effect of Carbonaceous Nanofillers on Strength Properties of Adhesive Lap Shear Joints /

By Ejaz, Hassan. . 252,p; 30,cm..

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INVESTIGATING THE EFFECT OF CARBONACEOUS NANOFILLERS ON STRENGTH PROPERTIES OF ADHESIVE LAP SHEAR JOINTS /

By Ejaz, Hassan . . 252p. , Adhesive joining presents a compelling substitute to traditional joining techniques, like welding and mechanical fastening. Adhesive bonding offers several advantages, such as the capability to construct lightweight and stiff structures, the ability to join various types of materials, offer improved fatigue performance, and a decrease in heat effects zones commonly associated with welding. However, lack of structural redundancy and moderate strength offered by adhesive joints still makes it an area of exploration for researchers as joint strength is significantly influenced by geometric, surface, manufacturing, and environmental parameters. In recent times, modification to the properties of host resin by the addition of nanofillers is a non-geometric parametric technique proven to be effective in improving the mechanical performance of adhesive joints. In literature, the effects of various fillers (metallic, nonmetallic) have been studied with varying rates of success. The conducted research aims to fill the gap in the non-metallic category by performing a systematic study of the effect of graphene nanoplatelets (GNPs), multiwalled carbon nanotubes (MWCNTs) and reduced graphene oxide (RGO) addition on a high viscous, high strength structural adhesive at various weight fractions of the nanofiller addition. The nanofillers including the functional components of GNPs and MWCNTs (COOH and NH2 functionalized) were added in weight fractions of 0.25, 0.5, 0.75 and 1 wt% in the adhesive. A comprehensive mixing method based on solution mixing technique was developed for uniform mixing of nanofillers in the host resin. The effects of filler addition on the dispersion characteristics, mechanical response of nanofiller/adhesive composite and strength characteristics of two different lap joint configurations were then investigated. The joints were fabricated using aluminum 5083 alloy where adherends were electrochemically treated prior to joining. Lap shear tests were conducted on Universal Testing Machine (UTM). Fourier-Transform Infrared Spectroscopy (FTIR) was utilized for the analysis of functional groups and chemical interaction of nanofillers with the adhesive. Variation in the cure kinetics was investigated using Differential Scanning Calorimetry (DSC). Ultraviolet-Visible Spectroscopy (UV-VIS-Nir) was carried out to quantitatively quantify the dispersion characteristics of nanofillers. ANOVA study was performed for the evaluation of data variation and interaction. Optical and Scanning Electron Microscopy (SEM) was utilized for the analysis of fracture surfaces, and the correlation between nano-reinforcement and strengthening mechanisms was critically discussed. A comprehensive comparison of the x mechanical behavior of bulk adhesive specimens and strength characteristics of lap joints reinforced with GNPs, MWCNTs and RGO was established. The novelty of the research is that, it introduces a pioneering exploration into the combined effects of functional and non-functional components of Carbon Nanotubes (CNTs), Graphene Nanoplatelets (GNPs), and Multi-Walled Carbon Nanotubes (MWCNTs) within high viscous structural adhesive. Unlike previous independent studies, our approach considers filler concentration, dispersion behavior, and diverse lap joint configurations, providing a holistic understanding of their impact on mechanical properties. The developed solution mixing technique ensures uniform nanofiller dispersion, and advanced characterization techniques offer unprecedented insights. This research not only addresses critical literature gaps but also provides a roadmap for tailoring adhesive properties, with wide-ranging implications for automotive, aerospace, marine, and construction industries. The result of the study depicted that the role of non-functionalized GNPs, MWCNTs in improving failure parameters in lap joints was superior to that of nonfunctionalized ones in general. This is a consequence of their superior dispersion properties and higher cross-linking density with the adhesive. However, in comparison between fillers, the strength improvement of lap joints reinforced with MWCNTs was superior to both GNPs and RGO. This is due the lateral length of the MWCNTs particles being greater than GNPs and MWCNTs which provided maximum shearing resistance out of the three nanofillers. The findings of this research can be applied to the aerospace and automotive sectors, construction and infrastructure and general adhesive industry where adhesive joints play a critical role in structural integrity. By incorporating carbonaceous nanofillers into epoxy adhesives, it is possible to enhance the strength and durability of adhesive bonds, resulting in improved performance and safety. 30cm..

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Effect of Stacking Sequence on Compression After Impact Performance of Basalt and Flax Fiber Reinforced Polymer Matrix Hybrid Composites /

By Abbas Dogar, Muhammad Mughees . . 98p. , Our world is vulnerable to the dangers of global warming and climate change because of their implications on economic, health, safety, water, ecosystem, infrastructure, and food production. Dangers of environmental changes have forced scientists and researchers to act against climate change to save our planet and protect biodiversity. Researchers and scientists are now highly interested in using natural fibers to reinforce composites for various engineering applications as they are eco-friendly, low cost, biodegradable and have renewable characteristics instead of synthetic fiber-based composites because of their high carbon footprint. Hybrid composites are combination of different types of reinforced fibers that provide a synergistic effect, which gives new and better properties. In the present research, the influence of five different stacking configurations on drop weight and compression after impact (CAI) characteristics of basalt and flax natural fiber-based hybrid composites is studied. The manufactured composite laminates have been experimentally characterized by drop weight impact and CAI tests at three different impact energies i.e. 30J, 45J and 60J. After the drop weight impact tests, indentation and damage measurements have been performed. CAI tests have been performed to find out the residual compressive strength of damaged laminates. During the drop weight impact test, symmetric configuration SS3 (B2F2B2F3B2F2B2) withstands the maximum force and highest bending stiffness. For all stacking configurations, at impact energies of 30 J and 45 J, a closed force–displacement curve was obtained. No perforation in the specimens is represented by partially closed curves. At 60J impact energy, perforation occurred in SS1 (B11F3B), SS2 (B6F3B6) and SS4 (BFB5FB5FB). SS1 (B11F3B) exhibits maximum indentation at all three energy levels whereas, SS5 (BF3B11) exhibits minimum indentation at all three energy levels and no damage at rear (non-impact) side was observed. From CAI results, it can be concluded that SS2 (B6F3B6) and SS3 (B2F2B2F3B2F2B2) are stronger than all other stacking configurations. The residual compressive strength of SS2 (B6F3B6) was higher at 30 J and 45 J than that of SS3 (B2F2B2F3B2F2B2), which is stronger at 60 J. 30cm.

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Low Velocity Impact Response of Composite Sandwich Structure with Hybrid Honeycomb Core /

By Ayub, Usman . . 70p. , Lightweight design is one of the key characteristics of engineering design, as light weight not only reduces operational cost but also reduces the impact on environment due to lesser fuel consumption. The use of sandwich structures is an important advancement in this regard, as sandwich structures use geometrically efficient design to reduce weight and offer superior properties like increased specific strength and stiffness, better fatigue and impact resistance, thermal conductivity and corrosion resistance as compared to their metallic counterparts. Sandwich structures, specifically with honeycomb core and fiber reinforced composite face sheets have been extensively used in aerospace, ship building, rail industry, military and auto motives. Impact loading, especially low velocity impact, is one of the most critical loading scenario for sandwich structures, as impact can cause strength degradation and barely visible damage, which can compromise the structural integrity. In recent times, most of the research has focused on improving the impact resistance of honeycomb sandwich structures by filling honeycomb with a filler material because the porous structure of honeycomb cells is the weakest region against impact loads, especially against oblique impact. This research also focuses on improving the impact resistance of conventional honeycomb by addition of aluminum grid and foam in honeycomb (HC) to produce a hybrid honeycomb (HHC) core sandwich panel. Impact tests are carried out using drop weight method at 30J and 45J for both conventional HC and HHC core and results are recorded in the form of force-displacement, force-time and energy time-response. The testing shows that HHC sustained higher peak force and lower displacement as compared to conventional HC core. The performance index, which compares the performance of HHC with conventional HC, for HHC-foam impact was 1.31 and 1.26 times for 30J and 45J respectively while for HHCgrid impact was 1.14 and 1.16 times for 30J and 45J respectively, highlighting the improved impact resistance of HHC core sandwich panels. Damage characterization through macroscopic damage analysis for damage on surface as well as internal damage was also performed highlighting the various damage modes like delamination, matrix cracking, core crushing and core buckling among other. 30cm.

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Effect of Hygrothermal Aging on Strength Performance of Cork Powder Reinforced Adhesive Joints /

By Butt, Muhammad Shahzaib . . 83p. , Adhesives play a crucial role across various industries and applications due to their ability to bond materials together. They are used in numerous ways, ranging from everyday household applications to industrial and specialized fields. Strength is most critical factor to analyze before using the adhesive. Various techniques have already been developed and many are being developed to predict and improve the strength of adhesive. Addition of cork powder to the structural adhesive could improve the strength of adhesive joints through mechanical interlocking between the cork cells and the molecules of adhesive. However, even after the nanofiller reinforcement, the strength of adhesive is significantly affected by environmental parameters like temperature and humidity. The present study investigated the effect of hygrothermal aging on the strength characteristics of lap joints made using cork powder reinforced adhesive. Lap joints were experimentally investigated under two different humidity levels 80% and 100% RH. The cork powder was added in concentration of 0.25wt.%, 0.5wt.%, 0.75wt.% and 1wt.%. to study the reinforcing effects. The lap joints were made using aluminum as adherend and it was observed that strength properties of lap joints were not significantly affected in lap joints under different humidity levels. The only impact was on 0.25% cork powder concentration samples where strength decreased sharply for conditioned samples. In case of elongation 0.25% and 1% cork powder reinforced samples had minimum values. When each sample is compared at different conditioning levels it was observed that conditioning improved elongation values of 0.5%, 0.75% & 1% samples. The failure modes were mostly cohesive with 1% samples exhibiting adhesive failure and neat samples were failed in mixed mode. 30cm.

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MXene Epoxy Nanocomposites for Enhanced Adhesive Bonding: Characterization and Performance Evaluation in Single-Lap Joints (SLJs) /

By Tarrab,Ali . . 102p. ; , Adhesive bonding is a critical technique in modern engineering, providing lightweight, highstrength joints for diverse applications in aerospace, automotive, and construction industries. This study explores the enhancement of epoxy-based adhesive performance through the incorporation of Ti₃C₂ MXene nanofillers, focusing on the tensile strength and thermal stability of single-lap joints (SLJs). Experimental testing was conducted on SLJs at three temperatures (25°C, 40°C, and 60°C) with varying MXene concentrations (0.25 wt.%, 0.50 wt.%, 0.75 wt.%, 1.00 wt.%, and 1.25 wt.%). The study revealed that MXene nanofillers significantly enhance adhesive performance. The highest tensile strength was observed at 1.0 wt.% MXene at 25°C and 1.25 wt.% MXene at 40°C and 60°C. Ti₃C₂ nanofiller reinforced adhesives demonstrated up to a 95.5% increase in tensile strength at elevated temperatures compared to neat epoxy, highlighting their superior thermal stability and mechanical reliability. At low concentrations (0.25 wt.%), the addition of MXene led to a reduction in failure load, emphasizing the need to optimize nanofiller content for maximum performance.While the results are promising, the study had some limitations. For instance, the Ti₃C₂ MXene used was unprocessed and not further etched into 2D nanosheets, which could potentially enhance its effectiveness. Additionally, the study did not assess long-term environmental resistance, such as exposure to moisture, UV radiation, or cyclic loading. To build on these findings, future work could explore functionalization of 2D Ti₃C₂ MXene, hybrid nanofiller systems (combining MXene with other nanomaterials), conduct durability tests under realistic environmental conditions, and scale up experiments to evaluate performance in industrial applications. These steps would provide a more comprehensive understanding of MXene's potential in advanced adhesive technologies. This research provides valuable insights into the design and optimization of MXene-reinforced adhesives, contributing to the development of lightweight, high-performance bonding solutions for modern engineering challenges. 30cm..

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Investigation of Bio-Hybrid Fiber Reinforced Composites Under Impact Loading /

By Masud, Manzar . . 224p. , The integration of natural and synthetic fibers in bio-hybrid fiber-reinforced polymer (HFRP) composites is gaining prominence in high-performance industries such as aerospace and automotive, driven by the demand for materials that balance mechanical performance, sustainability, and cost-effectiveness. This research adopts a dual approach, combining experimental testing with machine learning (ML) to investigate and optimize the mechanical performance of five composite laminates, including a pure carbon laminate and four carbon–flax HFRP configurations with symmetric and asymmetric stacking sequences. All laminates were evaluated through uniaxial tensile, compressive, lowvelocity impact (LVI) at energies from 30 to 75 J, and compression-after-impact (CAI) testing. The symmetric BH3 layup, with evenly distributed flax layers, demonstrated superior performance with only a 9% reduction in tensile strength compared to the carbon baseline while showing a 37.71% increase in failure strain, indicating enhanced energy absorption. Under compression, BH3 retained 86% of the carbon laminate’s strength and 81% of its modulus. In impact resistance, BH3 withstood energies up to 75 J, surpassing the carbon configuration. To evaluate performance and economic trade-offs, two indices were introduced i.e., the Impact Performance Index (IPI) and the Cost-Effectiveness Index (CEI). BH3 achieved the highest impact performance and a CEI comparable to that of the carbon laminate. Complementing the experimental work, an ML framework was employed using stacking sequence and impact energy as inputs, and peak impact force, damage area, and damage extension as outputs. Six algorithms were assessed, including decision tree (DT), random forest (RF), deep neural networks (DNN) with Adam and stochastic gradient descent (SGD) optimizers, and recurrent neural networks (RNN) with the same optimizers. The DT model with depth 8 and 28 leaf nodes performed best for peak force prediction, while the model with depth 6 and 23 leaf nodes was most accurate for damage area. An RNN with SGD and four hidden layers containing 70 neurons achieved the highest accuracy for damage extension. This integrated methodology demonstrates the potential of HFRP laminates to deliver high mechanical performance, improved damage tolerance, and enhanced sustainability for structural and impact-critical applications across automotive, aerospace, sporting, and construction sectors. 30cm.

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Impact localization on Composite Panel using Fiber-Bragg Gratings optical sensors /

By Arhaam Bin Touqeer, . . 70p. , The advancing use of composites in high stake environments, particularly aerospace industry demands strict monitoring of composite’s health over the entire period of life. Health of composite structures could easily be affected by internal damages like debonding or delamination that are invisible to naked eyes. These damages are normally caused by unexpected impact incidences mid-flight or during ground handling. If these damages are not identified timely, could lead to catastrophic failure. So, there is a need of a system that could timely identify and locate these damages in real-time. FiberBragg Grating sensors have gained confidence with their capability of measuring strains accurately along with their versatile and low-cost integration, particularly in composites. In this research work, FBG sensors have been used to identify and locate impact incidences on a composite laminate. Capability of FBG sensors of measuring strain wave initiated by impact incidence is being investigated. In order to extract quantitative information from strain response for impact localization, novel concepts like Empirical Mode Decomposition (EMD) and Hilbert Huan Spectrum have been used. Lastly, normalized values from spectrum are utilized and Artificial Neural Network has been applied to train the system to differentiate between different damage states. On the bases of predictions made by optimized ANN, comments on FBG sensors reliability have been presented and prospects for future research work discussed. 30cm.

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Investigation of Bio-Hybrid Fiber Reinforced Composites Under Impact Loading/

By Masud, Manzar.

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