Chapter 1 Introduction to Materials Science

Course Objectives properties & processing. Introduce fundamental concepts in Materials Science Provide the interrelationships among structure, properties & processing.

Learning Outcomes At the end of this course the students should be able to: Describe the classifications, structures & applications of metals, ceramics and polymers correctly. Analyse deformations behavior and strengthening mechanisms relying to its structure & properties of materials clearly. Apply Fick’s Law in calculating the diffusion process and its mechanism in solids properly.

Learning Outcomes At the end of this course the students should be able to: Demonstrate appropriate test methods in determining mechanical properties. Apply the relation between composition, microstructure and properties of metallic materials by using apposite phase diagram and heat treatment process.

Course Synopsis This course comprises the fundamentals of Materials Science and its applications, atomic structure, crystal structure, solidification, imperfections and solid diffusion, mechanical and physical properties, phase diagrams and transformation, synthesis, types and applications of materials.

Course References Callister W. D., 2008, Fundamentals of Materials Science and Engineering, 3rd Edition, John Wiley & Sons. Smith W. F., 2004, Foundation of Materials Science and Engineering, 4th Edition, McGraw Hill. Shackleford J. F. , 2000, Introduction to Materials Science for Engineers, 5th Edition, Prentice Hall. Budinski K. G. and Budinski M.G., 1999, Engineering Materials: Properties and Selection, 6th Edition, Butterworth-Heinemann UK. Askeland D. R., 1994, The Science and Engineering of Materials, 3rd Edition, PWS Publication Co.

Tutorial/Lab. Sections Lectures Lecturer: Wan Mohd Farid bin Wan Mohamad Time: 8 – 10 a.m (Tuesday) Place: BK 3, Fasa B Tutorial/Lab. Sections Group 1 Lecturer: Wan Mohd Farid Time: 2 – 5 p.m (Tuesday) Place: BK 1/MSTB Group 2 Lecturer: Sushiela Edayu Time: 2 – 5 p.m (Monday) Place: MCS /MSTB Technician (G1 & G2) Mahader bin Muhamad

Course Evaluations Criteria % Test 15 Assignment 5 Quiz Laboratory 12 Course work Test 1 Test (1½ hour) 15 Assignment 1 assignment Will be submitted 4 weeks after tutorial 1 Group presentation (week 15) 5 Quiz 2 Quizzes Laboratory 3 Informal Group Reports (hand written) Will be submitted 3 days after lab session 12 1 Formal Individual Report (hand written) Will be submitted 1 week after lab session 8 Final examination Exam 1 Final Exam (2 ½ hours) 40 Total 100

Hari Raya Aidilfitri Break Course Schedules Week 1,2 3,4 5,6 7 8,9 10,11 12 13,14 15 16 17, 18,19,20 Topic General Intro; Atomic Structure & Bonding Crystalline Structures; Polymers Defects; Diffusion Mid-Semester Break Mechanical Properties; Strength Mechanisms Failure; Phase Diagrams Hari Raya Aidilfitri Break Phase Transform; Appl. of Materials Physical Properties Revision & Group presentation Study week Final exam Chapter 1,2 3,4 5,6 7,8 9,10 11,12 13 Lectures: will highlight important portions of each chapter.

General Introduction What is materials science? Why should we know about it? Materials drive our society Stone Age Bronze Age Iron Age Now? Silicon Age? Polymer Age?

Example – Hip Implant With age or certain illnesses joints deteriorate. Particularly those with large loads (such as hip). Adapted from Fig. 22.25, Callister 7e.

Example – Hip Implant Requirements mechanical strength (many cycles) good lubricity biocompatibility Adapted from Fig. 22.24, Callister 7e. 12

Example – Hip Implant Adapted from Fig. 22.26, Callister 7e. 13

Hip Implant Key problems to overcome Ball fixation agent to hold acetabular cup cup lubrication material femoral stem – fixing agent (“glue”) must avoid any debris in cup Ball Acetabular Cup & Liner Femoral Stem Adapted from chapter-opening photograph, Chapter 22, Callister 7e. 14

Structure, Processing, & Properties • Properties depend on structure ex: hardness vs structure of steel martensitic (d) 30 mm 6 00 tempered martensite pearlite + proeutectoid ferrite 5 00 (c) 4 mm spheroidite Data obtained from Figs. 11.31(a) and 11.33 with 4 wt% C composition, and from Fig. 14.8 and associated discussion, Callister & Rethwisch 3e. Micrographs adapted from (a) Fig. 11.19; (b) Fig. 10.34;(c) Fig. 11.34; and (d) Fig. 11.22, Callister & Rethwisch 3e. 4 00 (b) 30 mm (a) 30 mm Hardness (BHN) 3 00 2 00 100 0.01 0.1 1 10 100 1000 Cooling Rate (ºC/s) • Processing can change structure ex: structure vs cooling rate of steel 15

Types of Materials Metals: Strong, ductile High thermal & electrical conductivity Opaque, reflective. Polymers/plastics: Covalent bonding  sharing of e’s Soft, ductile, low strength, low density Thermal & electrical insulators Optically translucent or transparent. Metals have high thermal & electrical conductivity because valence electrons are free to roam Ceramics: ionic bonding (refractory) – compounds of metallic & non-metallic elements (oxides, carbides, nitrides, sulfides) Brittle, glassy, elastic Non-conducting (insulators) 16

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. 17

ELECTRICAL • Electrical Resistivity of Copper: Resistivity, r T (°C) -200 -100 Cu + 3.32 at%Ni Cu + 2.16 at%Ni deformed Cu + 1.12 at%Ni 1 2 3 4 5 6 Resistivity, r (10-8 Ohm-m) Cu + 1.12 at%Ni “Pure” Cu Adapted from Fig. 12.8, Callister & Rethwisch 3e. (Fig. 12.8 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.) • Adding “impurity” atoms to Cu increases resistivity. • Deforming Cu increases resistivity. 18

THERMAL • Space Shuttle Tiles: • Thermal Conductivity of Copper: -- Silica fiber insulation offers low heat conduction. • Thermal Conductivity of Copper: -- It decreases when you add zinc! Adapted from chapter-opening photograph, Chapter 17, Callister & Rethwisch 3e. (Courtesy of Lockheed Missiles and Space Company, Inc.) Composition (wt% Zinc) Thermal Conductivity (W/m-K) 400 300 200 100 10 20 30 40 100 mm Adapted from Fig. 19.4W, Callister 6e. (Courtesy of Lockheed Aerospace Ceramics Systems, Sunnyvale, CA) (Note: "W" denotes fig. is on CD-ROM.) Adapted from Fig. 17.4, Callister & Rethwisch 3e. (Fig. 17.4 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.) 19

OPTICAL • Transmittance: -- Aluminum oxide may be transparent, translucent, or opaque depending on the material structure. single crystal polycrystal: low porosity high porosity Adapted from Fig. 1.2, Callister & Rethwisch 3e. (Specimen preparation, P.A. Lessing; photo by S. Tanner.) transparent translucent opaque 20

DETERIORATIVE • Heat treatment: slows • Stress & Saltwater... -- causes cracks! • Heat treatment: slows crack speed in salt water! “held at 160ºC for 1 hr before testing” increasing load crack speed (m/s) “as-is” 10 -10 -8 Alloy 7178 tested in saturated aqueous NaCl solution at 23ºC Adapted from Fig. 11.20(b), R.W. Hertzberg, "Deformation and Fracture Mechanics of Engineering Materials" (4th ed.), p. 505, John Wiley and Sons, 1996. (Original source: Markus O. Speidel, Brown Boveri Co.) Adapted from chapter-opening photograph, Chapter 16, Callister & Rethwisch 3e. (from Marine Corrosion, Causes, and Prevention, John Wiley and Sons, Inc., 1975.) 4 mm -- material: 7150-T651 Al "alloy" (Zn,Cu,Mg,Zr) Adapted from chapter-opening photograph, Chapter 11, Callister & Rethwisch 3e. (Provided courtesy of G.H. Narayanan and A.G. Miller, Boeing Commercial Airplane Company.) 21

SUMMARY Course Goals: • Use the right material for the job. • Understand the relation between properties, structure, and processing. • Recognize new design opportunities offered by materials selection. 22

End of Chapter 1