Transcription

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2 Design

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5 MATERIAIS

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8 History of Materials Science and Engineering

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17 FORÇAS TÉCNOLÓGICAS REVOLUCIONÁRIAS Têxtil Ferroviária Automotiva Computador Nanotecnologia Revolução industrial Revolução da informação Introdução da tecnologia Ampla utilização Final do crescimento rápido SIEMENS AG, CT, Manfred Weick Montag 1, Marz 2004 Grundlagen und State of he Art der Nanotehnologie.ppt Ref: Milunovich S. and Roy J.M.A.: The Next Small Thing RC Merril Lynch, 4 September, 2001

18 PROPRIEDADES Mecânicas Óticas Elétricas Magnéticas Térmicas

19 FIGURE 1.1 Materials science is the investigation of the relationships among structure, properties, processing, and performance of materials. (Mary Anne White. Properties of Materials.)

20 SÓLIDO = CRISTAL OU AMORFO?

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22 FIGURE 3.16 Schematic diagrams of the various stages in the solidification of a polycrystalline material; the square grids depict unit cells. (a) Small crystalline nuclei. (b) Growth of the crystallites; the obstruction of some grains that are adjacent to one another is also shown. (c) Upon completion of solidification, grains having irregular shapes have formed. (d) The grain structure as it would appear under the microscope; dark lines are the grain boundaries. (William D. Callister, JR. Materials Science and Engineering an Introduction, John Wiley & Sons, Inc.)

23 Monocrystalline Polycrystalline Amorphous

24 MATERIAIS Processo Estrutura Propriedades Desempenho

25 READING SCHEDULE Reading Schedule week chapter Introduction 0 - General Introduction, Atomic Bonding 1 1 e 2 Crystalline Structure; Imperfections 2 3 e 4 Diffusion; Mechanical Properties 3 5 e 6 Strengthening Mechanisms; Failure 4 7 e 8 Phase Diagrams 5 9 Kinetics & Phase Transformations 6 10 Processing & Applications of Metals 7 11 Structure, Properties, Process and Applications of Ceramics 8 12 e 13 Structure, Properties, Process of Polymers and Composites 9 15 e 16 Corrosion; Electrical & Thermal Properties 10 17, 18 e 19 Magnetic & Optical Properties e 21 Economic & Environmental Issues; Materials Selection CALLISTER JR., WILLIAM D., Ciência e Engenharia dos Materiais: Uma Introdução, 1a ed., Rio de Janeiro, LTC, 2002, ISBN: i

26 CHAPTER 1: MATERIALS SCIENCE & ENGINEERING Materials are... engineered structures...not blackboxes! Structure...has many dimensions... Structural feature atomic bonding missing/extra atoms crystals (ordered atoms) second phase particles crystal texturing Dimension (m) < >

27 Structure, Processing, & Properties Properties depend on structure ex: hardness vs structure of steel Hardness (BHN) (a) 30µm (b) 30µm (c) 4µm (d) Cooling Rate (C/s) Processing can change structure ex: structure vs cooling rate of steel 30µm Data obtained from Figs (a) and with 4wt%C composition, and from Fig and associated discussion, Callister 6e. Micrographs adapted from (a) Fig ; (b) Fig. 9.27;(c) Fig ; and (d) Fig , Callister 6e. 2

28 The Materials Selection Process 1. Pick Application Determine required Properties Properties: mechanical, electrical, thermal, magnetic, optical, deteriorative. 2. Properties Identify candidate Material(s) Material: structure, composition. 3. Material Identify required Processing Processing: changes structure and overall shape ex: casting, sintering, vapor deposition, doping forming, joining, annealing. 3

29 ELECTRICAL Electrical Resistivity of Copper: Resistivity, ρ (10-8 Ohm-m) Cu at%ni Cu at%ni deformed Cu at%ni Cu at%ni Pure Cu Adapted from Fig. 18.8, Callister 6e. (Fig adapted from: J.O. Linde, Ann Physik 5, 219 (1932); and C.A. Wert and R.M. Thomson, Physics of Solids, 2nd edition, McGraw-Hill Company, New York, 1970.) T ( C) Adding impurity atoms to Cu increases resistivity. Deforming Cu increases resistivity. 4

30 Space Shuttle Tiles: --Silica fiber insulation offers low heat conduction. 100µm THERMAL Fig. 19.0, Callister 6e. (Courtesy of Lockheed Missiles and Space Company, Inc.) Thermal Conductivity of Copper: --It decreases when Thermal Conductivity (W/m-K) Adapted from Fig. 19.4W, Callister 6e. (Courtesy of Lockheed Aerospace Ceramics Systems, Sunnyvale, CA) (Note: "W" denotes fig. is on CD-ROM.) you add zinc! Composition (wt%zinc) Adapted from Fig. 19.4, Callister 6e. (Fig is adapted from Metals Handbook: Properties and Selection: Nonferrous alloys and Pure Metals, Vol. 2, 9th ed., H. Baker, (Managing Editor), American Society for Metals, 1979, p. 315.) 5

31 Magnetic Storage: --Recording medium is magnetized by recording head. MAGNETIC Magnetic Permeability vs. Composition: --Adding 3 atomic % Si makes Fe a better recording medium! Fig , Callister 6e. (Fig is from J.U. Lemke, MRS Bulletin, Vol. XV, No. 3, p. 31, 1990.) Magnetization Fe+3%Si Fe Magnetic Field Adapted from C.R. Barrett, W.D. Nix, and A.S. Tetelman, The Principles of Engineering Materials, Fig. 1-7(a), p. 9, Electronically reproduced by permission of Pearson Education, Inc., Upper Saddle River, New Jersey. 6

32 OPTICAL Transmittance: --Aluminum oxide may be transparent, translucent, or opaque depending on the material structure. single crystal polycrystal: low porosity polycrystal: high porosity Adapted from Fig. 1.2, Callister 6e. (Specimen preparation, P.A. Lessing; photo by J. Telford.) 7

33 DETERIORATIVE Stress & Saltwater... --causes cracks! Adapted from Fig. 17.0, Callister 6e. (Fig is from Marine Corrosion, Causes, and Prevention, John Wiley and Sons, Inc., 1975.) Heat treatment: slows crack speed in salt water! crack speed (m/s) Adapted from Fig (b), R.W. Hertzberg, "Deformation and Fracture Mechanics of Engineering Materials" (4th ed.), p. 505, John Wiley and Sons, (Original source: Markus O. Speidel, Brown Boveri Co.) --material: 7150-T651 Al "alloy" (Zn,Cu,Mg,Zr) as-is held at 160C for 1hr before testing Alloy 7178 tested in saturated aqueous NaCl solution at 23C increasing load 4µm Adapted from Fig , Callister 6e. (Fig provided courtesy of G.H. Narayanan and A.G. Miller, Boeing Commercial Airplane Company.) 8

34 Course Goals: SUMMARY Use the right material for the job. Understand the relation between properties, structure, and processing. Recognize new design opportunities offered by materials selection. 9

35 Até aqui, tudo bem

36 Obrigado!