40 Questions
What was used by people in the Stone Age?
Stone, clay, skins, and wood
When did the use of iron and steel start?
1200 BC
What enabled the railroads and the building of the modern infrastructure?
A cheap process to make steel
What led to the understanding of how materials behave?
The discovery of quantum mechanics
What is the focus of Materials Science?
The relationship between properties and microstructure
According to what can materials be classified?
Structure, properties, use, and bonding
What are crystalline materials?
Metals and ceramics
What is Materials Engineering?
The knowledge base for engineering applications
What type of bonding is typically found in metals?
Electron sea
Which of the following materials is an example of a semiconductor?
Silicon
What is a characteristic of ceramics?
They are bound by Coulomb forces
What types of forces bind polymers together?
Covalent forces and van der Waals forces
What is a characteristic of composites?
They are made of different materials in intimate contact
What is the main characteristic of advanced materials?
They are designed for maximum performance
What is the term for materials that are biocompatible and used to replace human body parts?
Biomaterials
What is a characteristic of metals in terms of their physical properties?
They are usually strong and conduct electricity well
What type of bond is formed when electrons are shared between molecules?
Covalent bond
What is the condition for ionic bond formation?
Opposite charge on both ions
What is the formula for the attractive force between ions in an ionic bond?
F = q^2 / 4πε0r^2
What is the simplest example of a covalent bond?
H2 molecule
Why do atoms form covalent bonds?
To achieve a complete outer electron shell
What is the directionality of a covalent bond?
Directional
What is the energy in a covalent bond given by?
U = -m - n
Which elements are likely to form covalent bonds?
Non-metallic elements
What percentage of elements in the periodic table are metals?
80%
Which metal is not solid at room temperature?
Mercury
Why are the light metals (s block elements) chemically reactive?
Because they have only 1 or 2 electrons in the outer shell
What is a characteristic of noble gases?
They have a fully filled outer orbital
What is a characteristic of d-block elements?
They need only a few electrons to complete their outer shell
What is true about most non-metals?
They are gaseous
What is a characteristic of transition metals?
They are stronger and harder than other metals
Which group of elements are metalloids?
Elements B, Si, Ge, As, Sb, Te
What determines the different properties of graphite and diamond?
Arrangement of atoms at the atomic level
What is the main reason for studying materials in engineering disciplines?
All engineering disciplines need to know about materials
What is the primary concern for materials used in nuclear energy applications?
Solving the problem of residues or nuclear waste processing
What is the key requirement for materials used in hypersonic flight?
High strength, light weight, and high temperature resistance
What is the primary concern for materials used in optical communications?
Negligible absorption of light
What is the main goal of processing materials?
To alter the microstructure of the material to affect its properties
What is the primary requirement for materials used in civil construction?
High mechanical strength and corrosion resistance
What determines the mechanical properties of a material?
Arrangement of small grains of material at the microscopic level
Study Notes
Materials Science and Engineering
- Materials are classified into metals, alloys, polymers, ceramics, glasses, and composites.
- Metals have valence electrons that detach from atoms and spread in an "electron sea", making them strong, conductive, and shiny.
- Examples of metals include aluminum, steel, brass, and gold.
Bonding in Materials
- Metals bond through metallic bonding, where electrons are detached from atoms and shared among ions.
- Semiconductors bond through covalent bonding, where electrons are shared between atoms, and their electrical properties depend on minute impurities.
- Examples of semiconductors include silicon, germanium, and gallium arsenide.
- Ceramics bond through ionic bonding, where atoms behave like ions and are bound by Coulomb forces.
- Examples of ceramics include glass, porcelain, and many minerals.
- Polymers bond through covalent and weak van der Waals forces, making them lightweight and decomposable at moderate temperatures.
- Examples of polymers include plastics, nylon, Teflon, polyester, and rubber.
Classification of Materials
- Materials can be classified by structure, properties, or use.
- One way to classify materials is by the way atoms are bound together: crystalline, amorphous, type of bonding, molecular and crystal structure, and physical and mechanical properties.
History of Materials Science
- The development of civilization is associated with the discovery and use of new materials, such as stone, copper, bronze, iron, and steel.
- The discovery of quantum mechanics in the 1930s enabled an understanding of the atomic structure of materials and the development of materials science.
- Materials science combines physics, chemistry, and engineering to design and develop materials for specific applications.
Properties of Materials
- Materials respond to the environment through their mechanical, electrical, magnetic, thermal, optical, and chemical properties.
- Properties are determined by the arrangement of atoms at the atomic and microscopic levels.
- Processing of materials involves applying heat, mechanical forces, and other techniques to affect their microstructure and properties.
Importance of Materials Science
- Materials science is essential for advancing technologies, such as engine efficiency, nuclear energy, hypersonic flight, optical communications, and civil construction.
- Understanding materials is critical for all engineering disciplines, including metals, non-metals, and metalloids.
Atomic Structure and Bonding
- The periodic table classifies elements into metals, non-metals, and metalloids based on their outermost electron shell.
- Metals have partially filled outer shells, non-metals have fully filled outer shells, and metalloids exhibit properties of both metals and non-metals.
- Ionic bonding involves the transfer of electrons between atoms, resulting in a Coulomb attraction between positive and negative ions.
- Covalent bonding involves the sharing of electrons between atoms to form a bond, resulting in a directional bond.
This quiz covers the properties and types of materials, including metals, alloys, polymers, ceramics, glasses, and composites. Learn about the characteristics of each type of material.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
