MATSCI 201 Lecture 1 Introduction Fall 24 PDF

University of Science and Technology MATSCI 201 Fundamentals of Materials Science and Engineering LECTURE 1: INTRODUCTION By: Dr. Worood A. El-Mehalmey, PhD. 25/9/2024 Materials Science Program...

University of Science and Technology MATSCI 201 Fundamentals of Materials Science and Engineering LECTURE 1: INTRODUCTION By: Dr. Worood A. El-Mehalmey, PhD. 25/9/2024 Materials Science Program 1  MATSCI 201 Course Outline o Instructors: Dr. Worood A. El-Mehalmey, PhD. Title: Assistant Professor, Role: Lecture Instructor, and course coordinator Office Hours: Wednesday from 12:00-1:00pm o Teaching Assistants: Office Address: NB-F019. Mr. Ashraf Helmy and Ms. Mennallah Elzahid E-mail Address: [email protected] Office Hours: Mondays and Wednesdays from 1:00- 3:00pm Room: NB-F016. Dr. Mustafa Gamal, PhD. Title: Assistant Professor, E-mails: [email protected] Role: Laboratory Instructor Office Hours: Monday from 1:00-2:00pm Tutorial Sessions? Office Address: NB-F018. E-mail Address: [email protected] 2  MATSCI 201 Textbooks Materials Science and Engineering Authors: William D. Callister, Jr. and David G. Rethwisch. ISBN: 978-0-470-41997-7 Course Description This course introduces the students to the Fundamentals of Structure and Properties of Materials. 3 Course Learning Objectives (CLOs) ü Ability to understand the atomic structure & bonding and crystallographic planes & directions. ü The ability to determine the types of crystal systems and crystal defects. ü Ability to distinguish between different mechanical properties and their effect on materials behavior. ü Ability to differentiate between fracture mechanisms in ductile and brittle materials. ü Ability to understand phase diagrams especially the Iron-Iron Carbide phase diagram. ü Ability to characterize polymers types and their molecular structures and configurations.  MATSCI 201 You will learn about: material structure how structure dictates properties how processing can change structure This course will help you to: use materials properly realize new design opportunities with materials 5  MATSCI 201 Topics Covered 1 Introduction to Materials Science & Engineering, and Classification of Materials 2 Atomic Structure and Interatomic Bonding 3 The Structure of Crystalline Solids 4 Imperfections in Solids 5 Mechanical Properties of Metals 6 Dislocations and Strengthening Mechanisms 7 Phase Diagrams 8 Polymer Structure 6  MATSCI 201 Grading Mandatory to attend both System midterm exams, otherwise 60:40 will be taken Assignments (10%) Midterm Exams (30%) BEST ONE There will be three Two major exams of duration 1.5 hour assignments throughout the will be given to the students at the 6th semester, covering the and 12th week of the semester covering previous lecture topics. the subjects taught up the exam time. Quizzes (5%) Lab Reports (15%) Final Exam (40%) There will be three fifteen- Each student will prepare a lab At the end of the semester 2 minute quizzes throughout report on each conducted hours comprehensive exam the semester, covering the experiment (Total of 6 reports) will be given. previous lecture topics. 7 MATSCI 201 8  MATSCI 201 Lecture 1: Introduction o Materials Science and Engineering Definitions Importance o Classification of Materials Basic Materials ü Metals. ü Ceramics. ü Polymers. Composites. 9  MATSCI 201 Chapter 1: Introduction o Materials are probably more deep seated in our culture than most of us realize. Clothing. Transportation. Food Production (ingredients, sensing, processing and packaging) Buildings. o The development and advancement of societies have been intimately tied to the members’ ability to produce and manipulate materials to fill their needs. In fact, early civilizations have been designated by the level of their materials development. Stone Age It was not until relatively recent times that scientists came to understand Bronze Age the relationships between the structural elements of materials and Iron Age their properties. o Materials Utilization à was a selection process that involved deciding from a limited set of materials à the one best suited for an application due to its characteristics. 10  MATSCI 201 Materials Science and Engineering o It is useful to subdivide the discipline of materials science and engineering into materials science and materials engineering sub-disciplines. Materials Science à investigating the relationships that exist between the structures and properties of materials. Materials Engineering à on the basis of these structure– property correlations, designing or engineering the structure of a material to produce a predetermined set of properties 11  MATSCI 201 Materials Science and Engineering The Structure of a material usually relates to the arrangement of its internal components. Subatomic Subatomic structure involves electrons within the individual atoms and interactions with their nuclei. On an atomic level, structure encompasses the Microscopic organization of atoms or molecules relative to one another. The next larger structural realm, which contains large groups of atoms that are normally agglomerated together, is termed microscopic, meaning that which is subject to direct observation using some type of microscope. Finally, structural elements that can be viewed with the naked eye are termed macroscopic. Macroscopic 12  MATSCI 201 Materials Science and Engineering The Property is a material trait in terms of the kind and magnitude of response to a specific imposed stimulus. The properties of solid materials may be grouped into six different categories: Mechanical, Electrical, Thermal, Magnetic, Optical, and Deteriorative. Processing and Performance are important components involved in the science and engineering of materials. The structure of a material depends on how it is processed. A material’s performance is a function of its properties. 13  MATSCI 201 How Processing Changes Materials? o Example: Aluminum Oxide Left disk à High Degree of Perfection à Single Crystal à Transparent. Center disk à Numerous and Very Small Single Crystals à Translucent. (the boundaries between these small crystals scatter a portion of the light) Three thin disk specimens of aluminum oxide that have been placed over a Right disk à Many Small, Interconnected Crystals, and Large printed page in order to demonstrate Number of Very Small Pores or Void Spaces à opaque. their differences in light-transmittance characteristics. (pores also effectively scatter the reflected light) Each material was produced using a different processing technique. If optical transmittance is an important parameter relative to the ultimate in-service application, the performance of each material will be different. 14 Why Study Materials Science and MATSCI 201 Engineering? 1. To Tailor the Material through processing in order to obtain the required properties and performance. 2. To Avoid Catastrophic Failures à loss of money, and loss of lives. Example: The failure of many of the World War II Liberty ships à Three of them catastrophically split in half when cracks formed. When some normally ductile metal alloys are cooled to relatively low temperatures, they become susceptible to BRITTLE FRACTURE—that is, they experience a ductile-to-brittle transition upon cooling through a critical range of temperatures. These Liberty ships were constructed of steel that of them were deployed to the frigid North Atlantic, where the once ductile metal experienced brittle fracture when temperatures dropped to below the transition temperature. 15 Why Study Materials Science and MATSCI 201 Engineering? Example: The failure of Vega C rocket Launch few years ago. The investigation concluded that a component in the motor called a throat insert, made of carbon-carbon material designed to withstand high temperatures, suffered “thermo-mechanical over-erosion” during the launch. That insert regulates the flow of exhaust through the nozzle, and as it eroded the chamber pressure dropped, causing thrust to decrease. The erosion of the insert was linked to higher porosity of the carbon-carbon material. 16  Classification of Materials MATSCI 201 Basic Materials Composites Advanced Materials o Metals o Semiconductors o Ceramics o Biomaterials o Polymers o Smart Materials o Nano-engineered Materials Used In High-Technology Applications 17  MATSCI 201 Classification of Materials:Metals o Composition: They are composed of one or more metallic elements (e.g., iron, aluminum, copper, titanium, gold, nickel), and often also nonmetallic elements (e.g., carbon, nitrogen, oxygen) in relatively small amounts. o Structure: Atoms in metals and their alloys are arranged in very orderly manner. They are relatively dense. They have large number of non-localized electrons, these electrons are not bound to particular atoms. 18  MATSCI 201 Classification of Materials:Metals o Properties: They are relatively stiff, and strong. Yet are ductile (i.e., capable of large amounts of deformation without fracture). They are resistant to fracture. o Performance: They are extremely good conductors of electricity and heat, They are not transparent to visible light; a polished metal surface has a lustrous appearance. Some of the metals (i.e., Fe, Co, and Ni) have desirable magnetic properties. 19  MATSCI 201 Classification of Materials:Ceramics o Composition: They are compounds between metallic and nonmetallic elements; they are most frequently oxides, nitrides, and carbides. Examples: Aluminum oxide (or alumina,Al2O3), Silicon dioxide (or silica,SiO2), Silicon carbide (SiC), and Silicon nitride (Si3N4) How are they different from salts?! o Structure: They are less dense than metals, but denser than polymers and composites. 20  MATSCI 201 Classification of Materials:Ceramics o Properties: They are relatively stiff and strong—stiffness's and strengths are comparable to those of the metals. They are typically very hard. o Performance: They are typically insulator to the passage of heat and electricity. They are more resistant to high temperatures and harsh environments than are metals and polymers. They may be transparent, translucent, or opaque. Some of the oxide ceramics (e.g., Fe3O4) exhibit magnetic behavior. 21 Classification of Materials:Polymers o Composition: Many of them are organic compounds that are chemically based on carbon, hydrogen, and other non-metallic elements (i.e., O, N, and Si). Examples: Plastic and rubber materials. Polyethylene (PE), nylon, poly(vinyl chloride) (PVC), polycarbonate (PC), polystyrene (PS), and silicone rubber. o Structure: They have very large molecular structures, often chain like in nature, that often have a backbone of carbon atoms. These materials typically have low densities. 22  MATSCI 201 Classification of Materials:Polymers o Properties: They are not as stiff or strong as these other material types. They are extremely ductile and pliable (i.e., plastic), which means they are easily formed into complex shapes. They are relatively inert chemically and unreactive in a large number of environments. o Performance: à One major drawback to the They have Low electrical conductivities. polymers is their tendency to soften They are Non-magnetic. and/or decompose at modest temperatures, which, in some instances, limits their use. 23  MATSCI 201 One Material vs Combined Materials: Carbonated Beverages Containers The material used for Provide a barrier to the passage of carbon dioxide. this application must satisfy the following constraints: Be non-toxic, unreactive with the beverage, and, preferably, recyclable. Be relatively strong and capable of surviving a drop from a height of several feet. Be inexpensive, including the cost to fabricate the final shape. If optically transparent, retain its optical clarity. Be capable of being produced in different colors and/or adorned with decorative labels. 24  MATSCI 201 One Material vs Combined Materials: Carbonated Beverages Containers The Aluminum Strong, Very Good barrier to CO2 diffusion, Easily Recycled, Cools Alloy beverages rapidly, and Allows labels to be painted onto its surface. Relatively expensive to produce, and Optically Opaque The Glass Barrier to CO2 diffusion, Relatively inexpensive material, May be recycled Cracks and Fracture easily, and Relatively heavy The Plastic Relatively strong, May be made optically transparent, It is inexpensive, Lightweight, and It is recyclable It is not as impervious to the passage of CO2 25  MATSCI 201 Classification of Materials:Composites o It is composed of two (or more) individual materials that come from the categories previously discussed—metals, ceramics, and polymers. The design goal of a composite à To achieve a combination of properties that is not displayed by any single material To incorporate the best characteristics of each of the component materials. o Composites exist in nature Wood à strong and flexible cellulose fibers surrounded and held together by stiffer lignin. Bone à mixture of strong yet soft protein collagen and hard, brittle mineral apatite. 26  Boeing 787 Fuselage Classification of Materials:Composites o However, most of those we consider in our discussions are synthetic (or human-made) composites. 1. One of the most common and familiar composites is à Fiberglass ü In which small glass fibers are embedded within a polymeric material (normally an epoxy or polyester). ü The glass fibers are relatively strong and stiff (but also brittle), whereas the polymer is more flexible. Thus, fiberglass is relatively stiff, strong, and flexible. In addition, it has a low density. 2. Another technologically important material is à Carbon Fiber–reinforced Polymer (CFRP) Composite ü carbon fibers that are embedded within a polymer. ü These materials are stiffer and stronger than glass fiber–reinforced materials but more expensive. 27  Density Strength Resistance to Fracture Stiffness 28 28 Classify each of the following materials as to whether it is a metal, ceramic, or polymer. Justify each choice: (a) Brass (Cu-Zn) Metal (b) Magnesium oxide (MgO) Ceramic (c) Plexiglas® (Poly (methyl methacrylate) Polymer (d) Polychloroprene Polymer (e) Boron carbide (B4C) Ceramic (f) Cast iron Metal 29  MATSCI 201 In Summary! 1. Definition of Materials Science and Engineering. Materials Science Materials Engineering. 2. Materials Classifications; Basic, Composites, and advanced materials. Metals Ceramics. Polymers. Composites 30 MATSCI 201 31 31 MATSCI 201 32