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Articles 1 - 30 of 84

Full-Text Articles in Mechanical Engineering

Stress Concentration In Isotropic & Orthotropic Composite Plates With Center Circular Hole Subjected To Transverse Static Loading, Moon Banerjee, N. K. Jain, S. Sanyal Sep 2020

Stress Concentration In Isotropic & Orthotropic Composite Plates With Center Circular Hole Subjected To Transverse Static Loading, Moon Banerjee, N. K. Jain, S. Sanyal

International Journal of Mechanical and Industrial Engineering

The present study brings out the thorough analysis of isotropic and orthotropic fixed rectangular plate with center circular hole under transverse static loading condition. In this paper influence of stress concentration and deflection due to singularity for isotropic and orthotropic composite materials under different parametric conditions is obtained. The effect of thickness -to- width of plate (T/A) and diameter-to-width (D/A) ratio upon stress concentration factor (SCF) for different stresses were studied. An isotropic and one composite material were considered for analysis to determine the variation of SCF with elastic constants. Deflection in transverse direction were calculated and analyzed ...


A Performance Evaluation Of Leaf Spring Replacing With Composite Leaf Spring, Yogesh G. Nadargi, Deepak R. Gaikwad, Umesh D. Sulakhe Sep 2020

A Performance Evaluation Of Leaf Spring Replacing With Composite Leaf Spring, Yogesh G. Nadargi, Deepak R. Gaikwad, Umesh D. Sulakhe

International Journal of Mechanical and Industrial Engineering

The automobile industry has shown increased interest in the replacement of steel spring with fibre glass composite leaf spring due to high strength to weight ratio. Therefore the aim of this work is to reduce the weight and low cost fabrication of complete mono composite leaf spring and mono composite leaf spring with bonded end joints. Also, general study on the analysis and design. A single leaf with variable thickness and width for constant cross sectional area of unidirectional glass fibre reinforced plastic (GFRP) with similar mechanical and geometrical properties to the multi leaf spring, was designed, fabricated (hand- layup ...


Friction Stir Surfacing Of Cold Sprayed Bainitic Steel, P. Venkateswaran, Anant Kumar Mishra Sep 2020

Friction Stir Surfacing Of Cold Sprayed Bainitic Steel, P. Venkateswaran, Anant Kumar Mishra

International Journal of Applied Research in Mechanical Engineering

A superficial composite layer was produced by friction stir surfacing (FSS) on high strength bainitic steel, cold sprayed with the Cu-Y2O3-ZrO2 and Zn-Y2O3-ZrO2 metal-oxide powders. The FSS resulted consolidation of the elemental powders in the cold sprayed (CS) layer with some melting of Zn and Cu. The formation of a continuous, adherent layer on the steel surface facilitates closing of large pores at the coating-substrate interface. The consolidated layer on the steel surface showed comminution of the coarse oxide particles and concomitant reduction in the average particle size. The FSS resulted in a composite layer consisting of the hard martensite ...


Mechanical Behaviour Of Polypropylene And Human Hair Fibres And Polypropylene Reinforced Polymeric Composites, Sanjay Choudhry, Bhawana Pandey Sep 2020

Mechanical Behaviour Of Polypropylene And Human Hair Fibres And Polypropylene Reinforced Polymeric Composites, Sanjay Choudhry, Bhawana Pandey

International Journal of Mechanical and Industrial Engineering

Bio fibres have recently become eye-catching to researchers, engineers and scientist as an alternative reinforcement for FRP (fibre reinforced polymer) composite. Due to their low cost, fairly good mechanical properties, high aspect strength .Three to four ton of human hair fibre wasted in India annually .These fibre pose an environmental challenge In order to find commercial application the wasted human hair fibre mixed with polypropylene. Polypropylene based composite are prepared using hair fibre obtained from human hair. Human hair fibres are mixed into polypropylene (PP) at 3,5,10 and 15 % by wt. using two roll mills. The composite are ...


Elasto Buckling Behaviour Of Gfrp Laminated Plate With Central Holes, Ganesan. C, P.K. Dash Aug 2020

Elasto Buckling Behaviour Of Gfrp Laminated Plate With Central Holes, Ganesan. C, P.K. Dash

International Journal of Mechanical and Industrial Engineering

In various cases, it is roughly unavoidable to have holes in the plate elements for inspection, maintenance, and service purposes. In such cases, the presence of these holes redistributes the membrane stresses in the plates and may reduce their stability significantly. The buckling of such perforated plates has received the attention of many researchers over the past years. This paper deals with the buckling analysis of symmetrically and laminated composite plates under two sides simply supported and two sides free boundary condition. The effects on buckling load by various cut out shapes (circular, square and elliptical) and sizes are investigated ...


Compaction And Residual Stress Modeling In Composite Manufactured With Automated Fiber Placement, Von Clyde Jamora Apr 2020

Compaction And Residual Stress Modeling In Composite Manufactured With Automated Fiber Placement, Von Clyde Jamora

Mechanical & Aerospace Engineering Theses & Dissertations

Automated fiber placement is a state-of-the-art manufacturing process that allows for complex layup patterns and can quickly place, cut, and restart composite tows. However, with this type of manufacturing process layup defects are inevitable, and manufacturing defects propagate after curing. Process modeling is the considered approach for exploring the defect prediction. Two different but related works were conducted, which are the thermochemical and hyperelastic model and the residual deformation model. For the model before cooling, a hyperelastic model and a thermo-chemical were made to simulate the compaction and heat transfer. Temperature dependent properties that are a function of degree of ...


Jcati Composite Delaminator, Payden Coffman Jan 2020

Jcati Composite Delaminator, Payden Coffman

All Undergraduate Projects

Improvements need to be made to the existing delaminator system designed to crush proprietary Boeing 777 composite material. The current design incorporates a hydraulic system to achieve the high loads needed to separate material layers. The new system will need to be able to apply the same loads while at the same time allowing for a constant feed of material through the system. To achieve this, a “gear-like” crushing system will be implemented that will apply a high enough radial load into the material that will achieve delamination equal or greater than the previous design while at the same time ...


Study On Antibacterial Of Chitosan/Hydroxyapatite Doped Magnesium Composite As A Material For Bone Graft Applications, Andromeda Dwi Laksono, Teodoro A. Amatosa, Jr., Hilda Pebrianti Octaviana Sitorus, Wentika Putri Kusuma Asih, Sulistijono Sulistijono Dec 2019

Study On Antibacterial Of Chitosan/Hydroxyapatite Doped Magnesium Composite As A Material For Bone Graft Applications, Andromeda Dwi Laksono, Teodoro A. Amatosa, Jr., Hilda Pebrianti Octaviana Sitorus, Wentika Putri Kusuma Asih, Sulistijono Sulistijono

Makara Journal of Technology

Hydroxyapatite (HAp) is one of the constituent minerals of bone and teeth, that has been widely used for synthesizing bone graft. Due to the limitation on properties of the hydroxyapatite, it is doping with Magnesium (HAp-Mg). The addition of Chitosan (Chi) was expected to improve the antibacterial properties of HAp-Mg. The present research aims to study the influence of Chitosan with 0, 5, 15, and 25 wt% addition on biocompatibility properties of Chi/HAp-Mg composite. HAp-Mg was synthesized using the sol-gel method; meanwhile, Chi/HAp-Mg composite was manufactured by mixing Chitosan in acetic acid, and HAp-Mg was added into the ...


Double-Sided Corrugated Composite Tube And Axle Protective Mechanism For Railway Vehicles, Hozhabr Mozafari Nov 2019

Double-Sided Corrugated Composite Tube And Axle Protective Mechanism For Railway Vehicles, Hozhabr Mozafari

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Structural elements in transportation vehicles are exposed to different types of dynamic loadings and impact scenarios. Protecting passengers against injury and providing mechanisms to avoid impact induced damages to the critical components are the two hot topics in crashworthiness engineering. The presented research work includes two parts. The first part is about designing a novel double-sided composite corrugated tube that can be implemented in front chassis rail of ground vehicles to improve their crashworthiness against collision and car accidents. To maximize the controllable energy absorption of corrugation troughs as observed in the single sided corrugated (SSC) tube, we proposed and ...


High Enthalpy Storage Thermoset Network With Giant Stress And Energy Output In Rubbery State And Associated Applications, Jizhou Fan Jul 2019

High Enthalpy Storage Thermoset Network With Giant Stress And Energy Output In Rubbery State And Associated Applications, Jizhou Fan

LSU Doctoral Dissertations

In this study, a new shape memory thermoset network with giant stress and energy output in rubbery state is synthesized and studied firstly since the low output in stress and energy in rubbery state has been a bottleneck for wide-spread applications of thermoset shape memory polymers (SMPs). Traditionally, stress or energy storage in thermoset network is through entropy reduction by mechanical deformation or programming. We here report another mechanism for energy storage, which stores energy primarily through enthalpy increase by stretched bonds during programming. As compared to entropy-driven counterparts, which usually have a stable recovery stress from tenths to several ...


Design Of Natural Composite I-Beam For Sampe 2019, Brian Harkness Jun 2019

Design Of Natural Composite I-Beam For Sampe 2019, Brian Harkness

Honors Theses

In recent years, the demand for high performance, lightweight, fiber-reinforced composites have grown substantially. Fiberglass and carbon fiber have exemplary material properties that meet the demand and have set the industry standard for performance materials. Although these materials meet their design function, they suffer from high environmental impacts throughout their life cycle and are not cost effective to produce. Flax fiber composites have comparable properties to fiberglass but can be produced more efficiently and production requires much less energy consumption. Flax is a readily available, renewable material that will easily biodegrade once it is the end of its useful life ...


Effects Of Bio-Composites In Corrugated Sandwich Panels Under Edgewise Compression Loading, Jalen Christopher Mano May 2019

Effects Of Bio-Composites In Corrugated Sandwich Panels Under Edgewise Compression Loading, Jalen Christopher Mano

Master's Theses

Present day composite sandwich panels provide incredible strength. Their largest problem, however, is early bonding failure between the core and the skin. This is due to the low bonding surface area of present cores like honeycomb. Corrugated structures could provide a remedy for this with their much larger bonding surface area. Corrugated structures have extreme mechanical properties deeming them particularly useful in aerospace and automotive applications. However, previous research has shown that the stiffness of carbon fiber causes debonding and drastic failure when used as both a core and a skin. Bio-composites have properties that could strengthen the corrugated sandwich ...


Examination Of Ice Impactor And Mold, Matt Wilson Jan 2019

Examination Of Ice Impactor And Mold, Matt Wilson

Williams Honors College, Honors Research Projects

This research project investigates impact and damage response of composite sandwich structures impacted with solid ice at extreme low-temperature. Composite sandwich structures of carbon fiber reinforced polymer sheets lining a polyvinyl chloride foam core are subjected to low-velocity impact at arctic temperatures. This impact will be delivered by a solid ice tool-tip via a drop impact testing machine. Data and test results acquired will be composed into a research report that will be submitted to The University of Akron and published in a scientific journal. This project builds upon the earlier study by Elamin, Li, & Tan (2018).


Resistance To Helium Bubble Formation In Amorphous Sioc/Crystalline Fe Nanocomposite, Qing Su, Tianyao Wang, Jonathan Gigax, Lin Shao, Michael Nastasi Jan 2019

Resistance To Helium Bubble Formation In Amorphous Sioc/Crystalline Fe Nanocomposite, Qing Su, Tianyao Wang, Jonathan Gigax, Lin Shao, Michael Nastasi

Mechanical & Materials Engineering Faculty Publications

The management of radiation defects and insoluble He atoms represent key challenges for structural materials in existing fission reactors and advanced reactor systems. To examine how crystalline/amorphous interface, together with the amorphous constituents affects radiation tolerance and He management, we studied helium bubble formation in helium ion implanted amorphous silicon oxycarbide (SiOC) and crystalline Fe composites by transmission electron microscopy (TEM). The SiOC/Fe composites were grown via magnetron sputtering with controlled length scale on a surface oxidized Si (100) substrate. These composites were subjected to 50 keV He+ implantation with ion doses chosen to produce a 5 at ...


Composite Recycler: Frame, Alfonso Olivera Jan 2019

Composite Recycler: Frame, Alfonso Olivera

All Undergraduate Projects

How can composites be recycled? The Composite Recycler is an ongoing project that started in September 2017. The purpose of this project was to create a machine that will delaminate the composites, cut them, and heat them up to separate the resin from the composites so they can be recycled. A group was put together for the 2018-2019 academic year to further the project as a whole improve the operation of the device. The existing base was used as well as the cutter and the power sources. The upgrades included; a housing to support the transport rollers and changing from ...


Experimental Measurement Of Dielectric Properties Of Powdery Materials Using A Coaxial Transmission Line, Robert Tempke Jan 2019

Experimental Measurement Of Dielectric Properties Of Powdery Materials Using A Coaxial Transmission Line, Robert Tempke

Graduate Theses, Dissertations, and Problem Reports

This study proposes a standard methodology for coaxial dielectric property measurements of powdery materials (1-10GHz) using a coaxial transmission line. Four powdery materials with dielectric constants ranging from 3.5 to 70 (SiO2, Al2O3, CeO2, and TiO2) were experimentally investigated at varying volume loading fractions in a paraffin mixture. A statistically significant number of paraffin heterogeneous-mixtures was synthesized for all dielectric powders. The dielectric properties of the constitutive materials were determined using appropriate mixture equations. The sensitivity of the equations dielectric prediction to volume loading is discussed with guidance on selecting the best mixing equation. It was determined that low ...


Modeling And Simulation Of The Thermoforming Process In Thermoplastic-Matrix Composite Materials, Philip M. Bean Dec 2018

Modeling And Simulation Of The Thermoforming Process In Thermoplastic-Matrix Composite Materials, Philip M. Bean

Electronic Theses and Dissertations

Thermoplastic-matrix composite materials have unique advantages over traditional thermosets including faster processing, improved fracture toughness, and recyclability. These and other benefits have caused increasing interest in the use of these materials in both aerospace and automotive industries. Due to the differences in behavior, these materials require a different type of manufacturing process to thermoset matrix composites. This manufacturing process generally involves using pre manufactured tape-layers. These layers, containing both thermoplastic-matrix and fiber-reinforcement, are aligned to the desired orientation, and stacked up into a “tailored blank” using an automated tape layup machine. They are then heated to the thermoplastic melting temperature ...


Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe Dec 2018

Reinventing The Wheel, Esther K. Unti, Ahmed Z. Shorab, Patrick B. Kragen, Adam M. Menashe

Mechanical Engineering

Reinventing the Wheel selected tires and designed wheels for the 2018 Cal Poly, San Luis Obispo Formula SAE combustion vehicle. Available tire options were evaluated for steady-state and transient performance as well as vehicle integration. A single-piece composite wheel with hollow spokes was designed to meet stiffness, strength, and tolerance requirements. A detailed study of wheel loading and geometric structural efficiency was performed. Finite element analysis was used to iterate the geometry and laminate. A two-piece male mold was designed and machined to manufacture the wheel. Removable silicone inserts were used to create the hollow spokes.


Engineering Viscoelastic Behavior Of Carbon Fiber Reinforced Polymer Composites With Nanoparticles For Controlling Deployment Of Aerospace Structures, Mark Scherbarth Nov 2018

Engineering Viscoelastic Behavior Of Carbon Fiber Reinforced Polymer Composites With Nanoparticles For Controlling Deployment Of Aerospace Structures, Mark Scherbarth

Mechanical Engineering ETDs

The United States Air Force is focused on reducing mass and power consumption of spacecraft to increase their capabilities for space missions. Low mass and power consumption can be achieved by using composites with low density and high stiffness and utilizing few satellite components. One way to achieve reduced mass is by eliminating attendant deployment mechanisms consuming valuable power and mass allocations on spacecraft with deployable structures. Secondary systems are typically used to assist deployable space structures to ensure 100% success. A passively deployed space structure would be of great value to the Department of Defense and the commercial marketplace ...


Feasibility Of Hybrid Thermoplastic Composite-Concrete Load Bearing System, Camerin M. Seigars Aug 2018

Feasibility Of Hybrid Thermoplastic Composite-Concrete Load Bearing System, Camerin M. Seigars

Electronic Theses and Dissertations

Thermoplastic composites have many advantages over thermoset composites such as being recyclable, rapidly manufacturable, and more impact resistant. The goal of this thesis is to assess the feasibility of using thermoplastic composites in structural applications through literature review, mechanical testing, design of a load-bearing hybrid composite-concrete structures, and the implementation of thermoplastic composites for tensile reinforcement of concrete. The study had four objectives covering the stated goal.

  1. Conduct a literature review to direct thermoplastic material selection
  2. Characterize thermoplastic material mechanical properties using standardized mechanical testing
  3. Design a hybrid composite-reinforced concrete beam, and
  4. Develop thermoplastic shear connectors to develop composite action ...


Design Survey Of Laminated Composite I-Beam, Mrinmoy Saha Aug 2018

Design Survey Of Laminated Composite I-Beam, Mrinmoy Saha

All Graduate Plan B and other Reports

Composite I-beams are popular for high-strength low-weight applications. Learning the macro-mechanics and designing the composite I-beam properly are necessary. In this report, a design overview of the composite I-beam is discussed which is based on classical lamination theory where it includes the homogenization approach, the plane stress assumption and the Kirchhoff hypothesis. Using these assumptions, a method was developed to come up with the effective material properties of a beam. Formulas to calculate maximum deflection and maximum bending stress and shear stress and the stress concentration at the connection of web-flange are discussed which describe ways for designing and manufacturing ...


Novel Structural Health Monitoring And Damage Detection Approaches For Composite And Metallic Structures, Shervin Tashakori Jun 2018

Novel Structural Health Monitoring And Damage Detection Approaches For Composite And Metallic Structures, Shervin Tashakori

FIU Electronic Theses and Dissertations

Mechanical durability of the structures should be continuously monitored during their operation. Structural health monitoring (SHM) techniques are typically used for gathering the information which can be used for evaluating the current condition of a structure regarding the existence, location, and severity of the damage. Damage can occur in a structure after long-term operating under service loads or due to incidents. By detection of these defects at the early stages of their growth and nucleation, it would be possible to not only improve the safety of the structure but also reduce the operating costs. The main goal of this dissertation ...


Composite Suspension For A Mass Market Vehicle, Sarah M. Chapiama, Brian Auyeung, Jose Guerrero, Ethan Lau Jun 2018

Composite Suspension For A Mass Market Vehicle, Sarah M. Chapiama, Brian Auyeung, Jose Guerrero, Ethan Lau

Mechanical Engineering

Statement of Confidentiality: The complete senior project report was submitted to the project advisor and sponsor. The results of this project are of a confidential nature and will not be published at this time.


Open Source Multi-Head 3d Printer For Polymer-Metal Composite Component Manufacturing, J. Laureto, Joshua M. Pearce Mar 2018

Open Source Multi-Head 3d Printer For Polymer-Metal Composite Component Manufacturing, J. Laureto, Joshua M. Pearce

Joshua M. Pearce

As low-cost desktop 3D printing is now dominated by free and open source self-replicating rapid prototype (RepRap) derivatives, there is an intense interest in extending the scope of potential applications to manufacturing. This study describes a manufacturing technology that enables a constrained set of polymer-metal composite components. This paper provides (1) free and open source hardware and (2) software for printing systems that achieves metal wire embedment into a polymer matrix 3D-printed part via a novel weaving and wrapping method using (3) OpenSCAD and parametric coding for customized g-code commands. Composite parts are evaluated from the technical viability of manufacturing ...


Optimization Of Tow-Steered Composite Wind Turbine Blades For Static Aeroelastic Performance, Stephen Michael Barr Jan 2018

Optimization Of Tow-Steered Composite Wind Turbine Blades For Static Aeroelastic Performance, Stephen Michael Barr

Theses and Dissertations

The concept of passive aeroelastic tailoring is explored to maximize the performance of the NREL 5-MW wind turbine blade in a uniform flow. Variable-angle tow composite materials model the spanwise-variable wind turbine blade design to allow material-adaptive bend-twist coupling under static aerodynamic loading. A constrained optimization algorithm determines the composite fiber angles along the blade span for four inflow conditions ranging from cut-in to rated wind speeds. The computational fluid dynamics solver CRUNCH CFD and commercial finite element analysis solver Abaqus compute the static aerodynamic loads and structural deformations of the blades, respectively, which are passed iteratively between the solvers ...


Composite Cutting Device, Mikhail Minasyan Jan 2018

Composite Cutting Device, Mikhail Minasyan

All Undergraduate Projects

Title and Author: Composite Cutting Device by Misha Minasyan (Mechanical Engineering Technology)

As the aerospace industry innovates, so does the material that is being used. No longer are airplane manufacturers like Boeing depending on only various metals for making their wings. A transition over the past few years has been made to using composite materials because of there light weight and strength. The issue that composite material brings is that it cannot be recycled without processing. The current 777X made by Boeing has transitioned to used composite to manufacture their airplane wings.

A two student team developed two separate processes ...


Repurposing Carbon Fiber Composite Through Mechanical Means, Jason Morrow Jan 2018

Repurposing Carbon Fiber Composite Through Mechanical Means, Jason Morrow

All Undergraduate Projects

Composite waste from the 777 aircraft is a growing concern for Boeing and amounts to an excess of 600,000 pounds of highly valuable carbon fiber being thrown away. Reclaiming this material has been a long sought-after goal of Boeings as the current solution is ever expanding landfills. The two current methods of recycling composite waste are chemically and mechanically processing. The focus of this paper will be demonstrating the feasibility of mechanically processing composite waste to increase storage efficiency before chemically treating to reclaim the actual carbon fibers. This paper provides a two-stage solution for the recycling question. The ...


Fabrication And Characterizations Of Lagp/Peo Composite Electrolytes For All Solid-State Lithium-Ion Batteries, Jeremy J. Lee Jan 2018

Fabrication And Characterizations Of Lagp/Peo Composite Electrolytes For All Solid-State Lithium-Ion Batteries, Jeremy J. Lee

Browse all Theses and Dissertations

With the rise of electric vehicles and increasing dependence on mobile electronics, the demands for lithium-ion batteries have followed in tandem for their high energy and power densities. However, traditional lithium-ion batteries consisting of liquid electrolytes have limited operating temperatures and are susceptible to ignition and subsequent fires. Recently, battery research has diverged into solid state chemistry to address the aforementioned issues. In this research, we systematically investigate a series of ceramic/polymer lithium-ion conducting composite electrolytes, i.e. Li1.4Al0.4Ge1.6(PO4)3 /lithiated polyethylene oxide (LAGP/PEO). Lithiated PEO was prepared with two different lithium salts, LiBF4 ...


Material State Awareness For Composites Part Ii: Precursor Damage Analysis And Quantification Of Degraded Material Properties Using Quantitative Ultrasonic Image Correlation (Quic), Subir Patra, Sourav Banerjee Dec 2017

Material State Awareness For Composites Part Ii: Precursor Damage Analysis And Quantification Of Degraded Material Properties Using Quantitative Ultrasonic Image Correlation (Quic), Subir Patra, Sourav Banerjee

Faculty Publications

Material state awareness of composites using conventional Nondestructive Evaluation (NDE) method is limited by finding the size and the locations of the cracks and the delamination in a composite structure. To aid the progressive failure models using the slow growth criteria, the awareness of the precursor damage state and quantification of the degraded material properties is necessary, which is challenging using the current NDE methods. To quantify the material state, a new offline NDE method is reported herein. The new method named Quantitative Ultrasonic Image Correlation (QUIC) is devised, where the concept of microcontinuum mechanics is hybrid with the experimentally ...


Material State Awareness For Composites Part I: Precursor Damage Analysis Using Ultrasonic Guided Coda Wave Interferometry (Cwi), Subir Patra, Sourav Banerjee Dec 2017

Material State Awareness For Composites Part I: Precursor Damage Analysis Using Ultrasonic Guided Coda Wave Interferometry (Cwi), Subir Patra, Sourav Banerjee

Faculty Publications

Detection of precursor damage followed by the quantification of the degraded material properties could lead to more accurate progressive failure models for composite materials. However, such information is not readily available. In composite materials, the precursor damages—for example matrix cracking, microcracks, voids, interlaminar pre-delamination crack joining matrix cracks, fiber micro-buckling, local fiber breakage, local debonding, etc.—are insensitive to the low-frequency ultrasonic guided-wave-based online nondestructive evaluation (NDE) or Structural Health Monitoring (SHM) (~100–~500 kHz) systems. Overcoming this barrier, in this article, an online ultrasonic technique is proposed using the coda part of the guided wave signal, which is ...