DOCSLIB.ORG

Composite Material Concepts.Pptx

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Composite Material Concepts.Pptx Marine Composites Composite Material Concepts Marine Composites Webb Ins1tute Senior Elec1ve Spring, 2013 Composite Material Concepts Eric Greene, Naval Architect [email protected] 410.263.1348 410.703.3025 (cell) hp://ericgreeneassociates.com/webbins3tute.html Webb Ins3tute Senior Elec3ve – Spring 2013 page 0 Marine Composites What Are Composite Materials? Composite Material Concepts • A composite is the combinaon of materials that results in a greatly improved structure • Resin matrices transform from liquid to solid during fabricaon to “3e” the structure together • Fiberglass, Aramid, and carbon laminates with resins are eXamples of composites, as is plywood and other “engineered” wood products • Resin matrices are either “thermosets” that cure to solids through a non- reversible chemical process called “crosslinking” or “thermoplas3cs” that can be reformed when heated Webb Ins3tute Senior Elec3ve – Spring 2013 page 1 Marine Composites History of EngineereD Materials Composite Material Concepts Webb Ins3tute Senior Elec3ve – Spring 2013 page 2 Marine Composites History of Marine Composites Composite Material Concepts • Modern day composite materials were launched with phenolic resins almost 100 years ago • Fiberglass boat building began just after World War II when the Navy built a class of 28-foot personnel craft • During the 1960s, fiberglass boat building proliferated and with it came the rapid increase in boat ownership • From the 1960s to the present, advances in materials and fabrication techniques used in the pleasure craft industry have helped to reduce production costs and improve product quality • In 2000 MARINE COMPOSITES is published as a free online document Webb Ins3tute Senior Elec3ve – Spring 2013 page 3 Marine Composites Composites anD other Composite Material Concepts Structural Materials hLp://www-materials.eng.cam.ac.uk/mpsite/interac3ve_charts/strength-cost/NS6Chart.html Webb Ins3tute Senior Elec3ve – Spring 2013 page 4 Marine Composites Composites vs. Metals Composite Material Concepts Webb Ins3tute Senior Elec3ve – Spring 2013 page 5 Marine Composites Composites vs. Metals Composite Material Concepts Typical Comparison of Metal anD Composite Fague Damage Fa1gue Cycles or Time Salkind, M.J., “Fague of Composites,” Composite Materials: Tes3ng and Design, ASTM STP 497, 1972. Webb Ins3tute Senior Elec3ve – Spring 2013 page 6 Marine Composites Direconal Properes of Composites Composite Material Concepts The strength of composite fibers are dramacally reduced as the angle to the applied load is increased Webb Ins3tute Senior Elec3ve – Spring 2013 page 7 Marine Composites Effect of Fiber Angle Composite Material Concepts Effect on MoDulus of Fiber Angle Effect on Strength of Fiber Angle for UniDirec1onal E-glass for UniDirec1onal E-glass Holmes M Al-Khatat Q, “Structural Proper3es of GRP,” Composites July 1975 Webb Ins3tute Senior Elec3ve – Spring 2013 page 8 Marine Composites Strength and Sffness Characteriscs Composite Material Concepts Specific Strength and Sffness Stress/Strain Behavior Webb Ins3tute Senior Elec3ve – Spring 2013 page 9 Marine Composites Lamina-Laminate Definions Composite Material Concepts A lamina is a flat (or some3mes curved) arrangement of unidirec3onal (or woven) fibers suspended in a matriX material. A lamina is generally assumed to be orthotropic, and its thickness depends on the material from which it is made. A laminate is a stack of lamina oriented in a specific manner to achieve a desired result. The laminate’s mechanical proper3es depend on the proper3es of each lamina, as well as the order in which the lamina are stacked. Lamina Laminate Ronald D. Kriz, “Microstructure Lectures,” Virginia Polytechnic Ins3tute and State University Webb Ins3tute Senior Elec3ve – Spring 2013 page 10 Marine Composites Laminate Mechanical Proper1es Composite Material Concepts Webb Ins3tute Senior Elec3ve – Spring 2013 page 11 Marine Composites Material Allowables Composite Material Concepts The method for determining material allowables is to conduct a formal tes3ng program to determine the behavior of the material in its an3cipated in-service operang environment. • All material specimens for the tes3ng program should be fabricated under iden3cal condi3ons and processes as those an3cipated for the produc3on of the final structure. • The material tes3ng program is also to account for the stas3cal variability in actual composite material proper3es, both as manufactured and at the end of service life. • The test program shall be defined to develop B-Basis values, which are the values at which 90 percent of the populaon of the data is eXpected to fall, with a 95 percent confidence. Minimum requirement for the material test program (For panels to be considered from a separate batch, they must be shot separately with separately measured and miXed resin. Each panel from each batch is to be layed-up at different 3mes) Webb Ins3tute Senior Elec3ve – Spring 2013 page 12 Marine Composites Resin/Fiber Interface Composite Material Concepts Fiber Resin Interac1on Surface Characteriscs Surface treatment and sizing increase the fiber’s total surface area and porosity and alter its surface energy to improve adhesion between the fiber and the resin matriX in a composite. [Grafil Inc.] Material Engineering, May, 1978 p. 29 Webb Ins3tute Senior Elec3ve – Spring 2013 page 13 Marine Composites Micro-scale Fiber/Resin Interface Composite Material Concepts S.A. Hashim, J.A. Nisar, “An inves3gaon into failure and behaviour of GFRP pultrusion joints,” Internaonal Journal of Adhesion and Adhesives, Jan. 2013 Webb Ins3tute Senior Elec3ve – Spring 2013 page 14 Marine Composites Laminate Failure Composite Material Concepts • The key criterion for composite failure is the local strain to failure: ε’ a.k.a. elongaon at break and not stress (note that ε’ for the fiber/matriX interface i.e. transverse fibers ≅ 0.25 %) • MatriX cracking: • polyester resin ε’ = 0.9-4.0 % • vinyl ester ε’ = 1.0-4.0 % • epoXy resin ε’ = 1.0-3.5 % • phenolic resin ε’ = 0.5-1.0 % • Fiber fracture: • S/R-glass ε’ = 4.6-5.2 % • E-glass ε’ = 3.37 % • Kevlar 49 ε’ = 2.5 % • HS-carbon ε’ = 1.12 % • UHM-carbon ε’ = 0.38 John Summerscales, University of Plymouth, Oct. 2006 Webb Ins3tute Senior Elec3ve – Spring 2013 page 15 Marine Composites Elasc Proper1es Composite Material Concepts • Young’s moduli - uniaXial stress/uniXaial strain • Poisson’s rao - transverse strain/strain parallel to the load • Shear moduli - biaXial stress/biaXial strain • Bulk modulus - triaXial stress (pressure)/triaXial strain Subscript nomenclature transverse Y 2 through-thickness 3 Z X 1 axial, or John Summerscales, University of Plymouth, Oct. 2006 longitudinal Webb Ins3tute Senior Elec3ve – Spring 2013 page 16 Marine Composites Poisson’s Ra1o Composite Material Concepts Isotropic ν = - (strain normal to the applied stress) (strain parallel to the applied stress) -1 < ν < ½ Poisson’s ra1os for GRP high values low values Orthotropic: νij UD C1 UD C1 WR A2 WR A2 MaXwell’s reciprocal theorem νij √Ei/Ej νij √Ei/E j ν12E2 = ν21E1 ν12 0.308 1.606 0.140 0.942 Lemprière constraint ν21 0.123 0.623 0.109 1.061 ν ≤ (E /E )1/2 and ν ν ν < ½ ij i j 21 23 13 ν13 0.354 1.687 0.408 1.285 ν31 0.124 0.593 0.247 0.778 ν23 0.417 1.051 0.380 1.364 ν32 0.414 0.952 0.297 0.733 John Summerscales, University of Plymouth, Oct. 2006 Webb Ins3tute Senior Elec3ve – Spring 2013 page 17 Marine Composites Shear anD Bulk MoDulus Composite Material Concepts Shear MoDulus Bulk MoDulus Isotropic Orthotropic John Summerscales, University of Plymouth, Oct. 2006 Webb Ins3tute Senior Elec3ve – Spring 2013 page 18 Marine Composites Isotropy Composite Material Concepts Isotropic Plate In the study of mechanical proper3es of materials, isotropic means having iden3cal values of a property in all direc3ons. An orthotropic material has two or three mutually orthogonal twofold aXes of rotaonal symmetry so that its mechanical proper3es are, in general, different along S3ffness in 1-direc3on = s3ffness in 2- each aXis. direc3on = s3ffness in any direcon Orthotropic Plate Anisotropy can be defined as a difference, when measured along different aXes, in a material's physical or mechanical proper3es. Quasi-isotropic laminates eXhibit isotropic (that is, independent of direc3on) in-plane response but are not restricted to isotropic out-of-plane (bending) response. S3ffness in 1-direc3on >> s3ffness in 2- direc3on ≠ s3ffness in other direc3ons Webb Ins3tute Senior Elec3ve – Spring 2013 page 19 Marine Composites Isotropy Property Influence Composite Material Concepts Specific Strength versus Specific MoDulus Carl Zweben and Jean M. Hoffman, “Stronger and Lighter — hLp://hsc.csu.edu.au/engineering_studies/ Composites Make Their Mark,” MachineDesign.com Mar., 2008 focus/aero/2579/polymer_composites.html Webb Ins3tute Senior Elec3ve – Spring 2013 page 20 Marine Composites Quasi-isotropic Laminates Composite Material Concepts hLp://www.quartus.com/resources/white-papers/composites-101/ Webb Ins3tute Senior Elec3ve – Spring 2013 page 21 Marine Composites Mechanical Behavior of Composite Material Concepts Orthotropic Materials T Possible components of stress ac3ng as forces on a small differen3al element can be organized into a matriX format Ronald D. Kriz, “Microstructure Lectures,” Virginia Polytechnic Ins3tute and State University Webb Ins3tute Senior Elec3ve – Spring 2013 page 22 Marine Composites Orthotropic Elasc Properes Composite Material Concepts Young's Modulus, E, shear modulus, G, and Poisson's Rao, η, in each orthogonal plane can be used to classify the nine
Load more

Recommended publications
  • Green Composites in Architecture and Building Material Science
    Modern Applied Science; Vol. 9, No. 1; 2015 ISSN 1913-1844 E-ISSN 1913-1852 Published by Canadian Center of Science and Education Green Composites in Architecture and Building Material Science Ruslan Lesovik1, Yury Degtev1, Mahmud Shakarna1 & Anastasiya Levchenko1 1 Belgorod Shukhov State Technological University, 308012, Belgorod, Russia Correspondence: Ruslan Lesovik, Belgorod Shukhov State Technological University, 308012, Belgorod, Russia. Received: September 5, 2014 Accepted: September 8, 2014 Online Published: November 23, 2014 doi:10.5539/mas.v9n1p45 URL: http://dx.doi.org/10.5539/mas.v9n1p45 Abstract Currently, the topic of improvement of man`s live ability is becoming increasingly important. The notion of luxury living in the city includes social comfort, environment comfort (urban, natural landscape component). A wide range of small architectural forms of different architectural design and purpose is developed. The basic material for the production of small architectural forms is concrete. On optimal combination of negative and positive qualities, concrete is the most cost- effective material. In order to avoid increasing the price of hardscape, at their creating, it`s actual to use local raw materials and industrial waste. On their basis the modern high quality building materials are developed. To reduce prime costs of construction materials the technogenic raw materials are used. The solution of this actual problem possibly on the basis of expansion of a source of raw materials of the stone materials suitable for production
    [Show full text]
  • Ceramic Matrix Composites with Nano Technology–An Overview
    International Review of Applied Engineering Research. ISSN 2248-9967 Volume 4, Number 2 (2014), pp. 99-102 © Research India Publications http://www.ripublication.com/iraer.htm Ceramic Matrix Composites with Nano Technology–An Overview Saubhagya Sharma, Samresh Kumar Shashi and Vikram Tomar Department of Material Science & Nano Technology, University of Petroleum & Energy Studies, Dehradun, Uttrakhand. Abstract Ceramic matrix composites (CMCs) are promising materials for use in high temperature structural applications. This class of materials offers high strength to density ratios. Also, their higher temperature capability over conventional super alloys may allow for components that require little or no cooling. This benefit can lead to simpler component designs and weight savings. These materials can also contribute in increasing the operating efficiency due to higher operating temperatures being achieved. Using carbon/carbon composites with the help of Nanotechnology is more beneficial in structural engineering and can decrease the production cost. They can withstand high stresses and temperatures than the traditional alumina, silicon carbide which fracture easily under mechanical loads Fundamental work in processing, characterization and analysis is important before the structural properties of this new class of Nano composites can be optimized. The fields of the Nano composite materials have received a lot of attention to scientists and engineers in recent years. The fabrication of such composites using Nano technology can make a revolution in the field of material science engineering and can make the composites able to be used in long lasting applications. 1. Introduction As we know that Composite materials are the type of materials that are formed by combining two or more materials of different physical and chemical properties.
    [Show full text]
  • Hybrid Self-Reinforced Composite Materials Based on Ultra-High Molecular Weight Polyethylene
    materials Article Hybrid Self-Reinforced Composite Materials Based on Ultra-High Molecular Weight Polyethylene Dmitry Zherebtsov 1,* , Dilyus Chukov 1 , Eugene Statnik 2 and Valerii Torokhov 1 1 Center of Composite Materials, National University of Science and Technology “MISiS”, 119049 Moscow, Russia; [email protected] (D.C.); [email protected] (V.T.) 2 Skolkovo Institute of Science and Technology, 143026 Moscow, Russia; [email protected] * Correspondence: [email protected] Received: 2 March 2020; Accepted: 3 April 2020; Published: 8 April 2020 Abstract: The properties of hybrid self-reinforced composite (SRC) materials based on ultra-high molecular weight polyethylene (UHMWPE) were studied. The hybrid materials consist of two parts: an isotropic UHMWPE layer and unidirectional SRC based on UHMWPE fibers. Hot compaction as an approach to obtaining composites allowed melting only the surface of each UHMWPE fiber. Thus, after cooling, the molten UHMWPE formed an SRC matrix and bound an isotropic UHMWPE layer and the SRC. The single-lap shear test, flexural test, and differential scanning calorimetry (DSC) analysis were carried out to determine the influence of hot compaction parameters on the properties of the SRC and the adhesion between the layers. The shear strength increased with increasing hot compaction temperature while the preserved fibers’ volume decreased, which was proved by the DSC analysis and a reduction in the flexural modulus of the SRC. The increase in hot compaction pressure resulted in a decrease in shear strength caused by lower remelting of the fibers’ surface. It was shown that the hot compaction approach allows combining UHMWPE products with different molecular, supramolecular, and structural features.
    [Show full text]
  • Improving Plastics Management: Trends, Policy Responses, and the Role of International Co-Operation and Trade
    Improving Plastics Management: Trends, policy responses, and the role of international co-operation and trade POLICY PERSPECTIVES OECD ENVIRONMENT POLICY PAPER NO. 12 OECD . 3 This Policy Paper comprises the Background Report prepared by the OECD for the G7 Environment, Energy and Oceans Ministers. It provides an overview of current plastics production and use, the environmental impacts that this is generating and identifies the reasons for currently low plastics recycling rates, as well as what can be done about it. Disclaimers This paper is published under the responsibility of the Secretary-General of the OECD. The opinions expressed and the arguments employed herein do not necessarily reflect the official views of OECD member countries. This document and any map included herein are without prejudice to the status of or sovereignty over any territory, to the delimitation of international frontiers and boundaries and to the name of any territory, city or area. For Israel, change is measured between 1997-99 and 2009-11. The statistical data for Israel are supplied by and under the responsibility of the relevant Israeli authorities. The use of such data by the OECD is without prejudice to the status of the Golan Heights, East Jerusalem and Israeli settlements in the West Bank under the terms of international law. Copyright You can copy, download or print OECD content for your own use, and you can include excerpts from OECD publications, databases and multimedia products in your own documents, presentations, blogs, websites and teaching materials, provided that suitable acknowledgment of OECD as source and copyright owner is given.
    [Show full text]
  • Multidisciplinary Design Project Engineering Dictionary Version 0.0.2
    Multidisciplinary Design Project Engineering Dictionary Version 0.0.2 February 15, 2006 . DRAFT Cambridge-MIT Institute Multidisciplinary Design Project This Dictionary/Glossary of Engineering terms has been compiled to compliment the work developed as part of the Multi-disciplinary Design Project (MDP), which is a programme to develop teaching material and kits to aid the running of mechtronics projects in Universities and Schools. The project is being carried out with support from the Cambridge-MIT Institute undergraduate teaching programe. For more information about the project please visit the MDP website at http://www-mdp.eng.cam.ac.uk or contact Dr. Peter Long Prof. Alex Slocum Cambridge University Engineering Department Massachusetts Institute of Technology Trumpington Street, 77 Massachusetts Ave. Cambridge. Cambridge MA 02139-4307 CB2 1PZ. USA e-mail: [email protected] e-mail: [email protected] tel: +44 (0) 1223 332779 tel: +1 617 253 0012 For information about the CMI initiative please see Cambridge-MIT Institute website :- http://www.cambridge-mit.org CMI CMI, University of Cambridge Massachusetts Institute of Technology 10 Miller’s Yard, 77 Massachusetts Ave. Mill Lane, Cambridge MA 02139-4307 Cambridge. CB2 1RQ. USA tel: +44 (0) 1223 327207 tel. +1 617 253 7732 fax: +44 (0) 1223 765891 fax. +1 617 258 8539 . DRAFT 2 CMI-MDP Programme 1 Introduction This dictionary/glossary has not been developed as a definative work but as a useful reference book for engi- neering students to search when looking for the meaning of a word/phrase. It has been compiled from a number of existing glossaries together with a number of local additions.
    [Show full text]
  • TSCA Inventory Representation for Products Containing Two Or More
    mixtures.txt TOXIC SUBSTANCES CONTROL ACT INVENTORY REPRESENTATION FOR PRODUCTS CONTAINING TWO OR MORE SUBSTANCES: FORMULATED AND STATUTORY MIXTURES I. Introduction This paper explains the conventions that are applied to listings of certain mixtures for the Chemical Substance Inventory that is maintained by the U.S. Environmental Protection Agency (EPA) under the Toxic Substances Control Act (TSCA). This paper discusses the Inventory representation of mixtures of substances that do not react together (i.e., formulated mixtures) as well as those combinations that are formed during certain manufacturing activities and are designated as mixtures by the Agency (i.e., statutory mixtures). Complex reaction products are covered in a separate paper. The Agency's goal in developing this paper is to make it easier for the users of the Inventory to interpret Inventory listings and to understand how new mixtures would be identified for Inventory inclusion. Fundamental to the Inventory as a whole is the principle that entries on the Inventory are identified as precisely as possible for the commercial chemical substance, as reported by the submitter. Substances that are chemically indistinguishable, or even identical, may be listed differently on the Inventory, depending on the degree of knowledge that the submitters possess and report about such substances, as well as how submitters intend to represent the chemical identities to the Agency and to customers. Although these chemically indistinguishable substances are named differently on the Inventory, this is not a "nomenclature" issue, but an issue of substance representation. Submitters should be aware that their choice for substance representation plays an important role in the Agency's determination of how the substance will be listed on the Inventory.
    [Show full text]
  • A Study of the Mechanical Properties of Composite Materials with a Dammar-Based Hybrid Matrix and Two Types of Flax Fabric Reinforcement
    polymers Article A Study of the Mechanical Properties of Composite Materials with a Dammar-Based Hybrid Matrix and Two Types of Flax Fabric Reinforcement Dumitru Bolcu † and Marius Marinel St˘anescu*,† Department of Mechanics, University of Craiova, 165 Calea Bucure¸sti,200620 Craiova, Romania; [email protected] * Correspondence: [email protected]; Tel.: +40-740-355-079 † These authors contributed equally to this work. Received: 7 July 2020; Accepted: 22 July 2020; Published: 24 July 2020 Abstract: The need to protect the environment has generated, in the past decade, a competition at the producers’ level to use, as much as possible, natural materials, which are biodegradable and compostable. This trend and the composite materials have undergone a spectacular development of the natural components. Starting from these tendencies we have made and studied from the point of view of mechanical and chemical properties composite materials with three types of hybrid matrix based on the Dammar natural hybrid resin and two types of reinforcers made of flax fabric. We have researched the mechanical properties of these composite materials based on their tensile strength and vibration behavior, respectively. We have determined the characteristic curves, elasticity modulus, tensile strength, elongation at break, specific frequency and damping factor. Using SEM (Scanning Electron Microscopy) analysis we have obtained images of the breaking area for each sample that underwent a tensile test and, by applying FTIR (Fourier Transform Infrared Spectroscopy) and EDS (Energy Dispersive Spectroscopy) analyzes, we have determined the spectrum bands and the chemical composition diagram of the samples taken from the hybrid resins used as a matrix for the composite materials under study.
    [Show full text]
  • Chapter 2 the Solid Materials of the Earth's Surface
    CHAPTER 2 THE SOLID MATERIALS OF THE EARTH’S SURFACE 1. INTRODUCTION 1.1 To a great extent in this course, we will be dealing with processes that act on the solid materials at and near the Earth’s surface. This chapter might better be called “the ground beneath your feet”. This is the place to deal with the nature of the Earth’s surface materials, which in later sections of the chapter I will be calling regolith, sediment, and soil. 1.2 I purposely did not specify any previous knowledge of geology as a prerequisite for this course, so it is important, here in the first part of this chapter, for me to provide you with some background on Earth materials. 1.3 We will be dealing almost exclusively with the Earth’s continental surfaces. There are profound geological differences between the continents and the ocean basins, in terms of origin, age, history, and composition. Here I’ll present, very briefly, some basic things about geology. (For more depth on such matters you would need to take a course like “The Earth: What It Is, How It Works”, given in the Harvard Extension program in the fall semester of 2005– 2006 and likely to be offered again in the not-too-distant future.) 1.4 In a gross sense, the Earth is a layered body (Figure 2-1). To a first approximation, it consists of concentric shells: the core, the mantle, and the crust. Figure 2-1: Schematic cross section through the Earth. 73 The core: The core consists mostly of iron, alloyed with a small percentage of certain other chemical elements.
    [Show full text]
  • Investigating the Mechanical Properties of Polyester- Natural Fiber Composite
    International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 07 | July -2017 www.irjet.net p-ISSN: 2395-0072 INVESTIGATING THE MECHANICAL PROPERTIES OF POLYESTER- NATURAL FIBER COMPOSITE OMKAR NATH1, MOHD ZIAULHAQ2 1M.Tech Scholar,Mech. Engg. Deptt.,Azad Institute of Engineering & Technology,Uttar Pradesh,India 2Asst. Prof. Mechanical Engg. Deptt.,Azad Institute of Engineering & Technology, Uttar Pradesh,India ------------------------------------------------------------------------***----------------------------------------------------------------------- Abstract : Reinforced polymer composites have played an Here chemically treated and untreated fibres were mixed ascendant role in a variety of applications for their high separately with polyester matrix and by using hand lay –up meticulous strength and modulus. The fiber may be synthetic technique these reinforced composite material is moulded or natural used to serves as reinforcement in reinforced into dumbbell shape. Five specimens were prepared in composites. Glass and other synthetic fiber reinforced different arrangement of natural fibres and glass fiber in composites consists high meticulous strength but their fields of order to get more accurate results. applications are restrained because of their high cost of production. Natural fibres are not only strong & light weight In the present era of environmental consciousness, but mostly cheap and abundantly available material especially more and more material are emerging worldwide, Efficient in central uttar Pradesh region and north middle east region. utilization of plant species and utilizing the smaller particles Now a days most of the automotive parts are made with and fibers obtained from various lignocellulosic materials different materials which cannot be recycled. Recently including agro wastes to develop eco-friendly materials is European Union (E.U) and Asian countries have released thus certainly a rational and sustainable approach.
    [Show full text]
  • Review of Thermal Properties of Graphene and Few-Layer
    Zhong Yan, Denis L. Nika and Alexander A. Balandin (invited review, submitted in 2014) INVITED REVIEW PAPER Review of Thermal Properties of Graphene and Few-Layer Graphene: Applications in Electronics Zhong Yan1, Denis L. Nika1,2 and Alexander A. Balandin1,3 1Nano-Device Laboratory, Department of Electrical Engineering and Materials Science and Engineering Program, Bourns College of Engineering, University of California – Riverside, Riverside, California, 92521 USA 2E. Pokatilov Laboratory of Physics and Engineering of Nanomaterials, Department of Physics and Engineering, Moldova State University, Chisinau, MD-2009, Republic of Moldova 3Quantum Seed LLC, 1190 Columbia Avenue, Riverside, California 92507 USA Abstract We review thermal properties of graphene and few-layer graphene, and discuss applications of these materials in thermal management of advanced electronics. The intrinsic thermal conductivity of graphene – among the highest of known materials – is dominated by phonons near the room temperature. The examples of thermal management applications include the few-layer graphene heat spreaders integrated near the heat generating areas of the high-power density transistors. It has been demonstrated that few-layer graphene heat spreaders can lower the hot-spot temperature during device operation resulting in improved performance and reliability of the devices. Keywords: graphene, thermal conductivity, heat spreaders, thermal management 1 Zhong Yan, Denis L. Nika and Alexander A. Balandin (invited review, submitted in 2014) I. Introduction Thermal management represents a major challenge in the state-of-the-art electronics due to rapid increase of power densities [1, 2]. Efficient heat removal has become a critical issue for the performance and reliability of modern electronic, optoelectronic, photonic devices and systems.
    [Show full text]
  • Introduction to Material Science and Engineering Presentation.(Pdf)
    Introduction to Material Science and Engineering Introduction What is material science? Definition 1: A branch of science that focuses on materials; interdisciplinary field composed of physics and chemistry. Definition 2: Relationship of material properties to its composition and structure. What is a material scientist? A person who uses his/her combined knowledge of physics, chemistry and metallurgy to exploit property-structure combinations for practical use. What are materials? What do we mean when we say “materials”? 1. Metals 2. Ceramics 3. Polymers 4. Composites - aluminum - clay - polyvinyl chloride (PVC) - wood - copper - silica glass - Teflon - carbon fiber resins - steel (iron alloy) - alumina - various plastics - concrete - nickel - quartz - glue (adhesives) - titanium - Kevlar semiconductors (computer chips, etc.) = ceramics, composites nanomaterials = ceramics, metals, polymers, composites Length Scales of Material Science • Atomic – < 10-10 m • Nano – 10-9 m • Micro – 10-6 m • Macro – > 10-3 m Atomic Structure – 10-10 m • Pertains to atom electron structure and atomic arrangement • Atom length scale – Includes electron structure – atomic bonding • ionic • covalent • metallic • London dispersion forces (Van der Waals) – Atomic ordering – long range (metals), short range (glass) • 7 lattices – cubic, hexagonal among most prevalent for engineering metals and ceramics • Different packed structures include: Gives total of 14 different crystalline arrangements (Bravais Lattices). – Primitive, body-centered, face-centered Nano Structure – 10-9 m • Length scale that pertains to clusters of atoms that make up small particles or material features • Show interesting properties because increase surface area to volume ratio – More atoms on surface compared to bulk atoms – Optical, magnetic, mechanical and electrical properties change Microstructure – 10-6 • Larger features composed of either nanostructured materials or periodic arrangements of atoms known as crystals • Features are visible with high magnification in light microscope.
    [Show full text]
  • Materials for Polymer Composites
    Module 2 - Materials For Polymer Composites Module 2 - Materials for Polymer Composites Introduction Major constituents in a fiber-reinforced composite material are the reinforcing fibers and a matrix, which acts as a binder for the fibers. Other constituents that may also be found are coupling agents, coatings, and fillers. Coupling agents and coatings are applied on the fibers to improve their wetting with the matrix as well as to promote bonding across the fiber–matrix interface. Both in turn promote a better load transfer between the fibers and the matrix. Fillers are used with some polymeric matrices primarily to reduce cost and improve their dimensional stability. Manufacturing of a composite structure starts with the incorporation of a large number of fibers into a thin layer of matrix to form a lamina (ply). The thickness of a lamina is usually in the range of 0.1–1 mm. If continuous (long) fibers are used in making the lamina, they may be arranged either in a unidirectional orientation (i.e., all fibers in one direction, Figure 2.1a), in a bidirectional orientation (i.e., fibers in two directions, usually normal to each other, Figure 2.1b), or in a multidirectional orientation (i.e., fibers in more than two directions, Figure 2.1c). The bi- or multidirectional orientation of fibers is obtained by weaving or other processes used in the textile industry. For a lamina containing unidirectional fibers, the composite material has the highest strength and modulus in the longitudinal direction of the fibers. However, in the transverse direction, its strength and modulus are very low.
    [Show full text]