Classification, Structure, and Solidification Of Materials Flashcards
Metals, ceramics, semiconductors, and polymers are the four major groups of which type of materials?
Engineering materials
An example of a substitutional alloy, one where a specific atom in a metal has been replaced by another from a different element, would be
Brass
A basic property of metal that allows it to be extensively deformed under compression without fracturing at room temperature and relatively high strain rates is called
Malleability
Large quantities of metals are used in engineering materials because of
The wide variety of mechanical properties and ability to conduct electricity and heat.
What type of engineering material has the ability to keep its strength at high temperature(higherthan most metals and polymers), and is resistant to most chemicals because of the strength and stability of its bonds
Ceramics
Thermistors are made from which of the following
Intrinsic semiconductors
Diodes, light-emitting diodes, and transistors are all examples of which of the following
Extrinsic semiconductors
Recycling and re-melting are two of the big advantages of which type of polymer
Thermoplastic
Examples of natural composites would include which of the following?
Wood and granite
The properties of composites are greatly influenced by the type of matrix and
The type, shape, and size of the reinforcement materials used.
Despite the advances in the use of composite materials, the largest quantity of composites compromises
Concrete
Nearly inert, porous growth, surface reactive, and absorbable are all examples of what broad classification of engineering materials?
Biomaterials
Materials that change shape with temperature, change dimension with application of an electrical impulse, or respond to strain by producing a magnetic field are called
Smart materials
The number of protons in the nucleus of an atom is referred to A s which of the following?
Atomic or Z-number
Regarding the elements on the periodic table, a neutral atom has
The same number of protons as electrons
Atoms of the same element that have a different number of neutrons in there nucleus are referred to as
Isotopes
Ionic, covalent,and metallic bonding are all examples of what general type of chemical bonding?
Strong bonds
Which type of bonds always found in compounds that contain both metallic and nonmetallic elements?
Ionic
Two atoms that are covalently bonded will share at least
One electron
The three most common lattice structures for metals include which of the following
Body-centered cubic, face centerd cubic, hexagonal close packed.
Iron has a body-centered cubic structure at room temperature, but as it is heated thin structure changes to
Face-centered cubic
A material that has no well-defined crystalline structure is often described as _______________in nature
Amorphous
Prior to the onset of yield, ratio between stress (amount of forse per unit area) and strain ( change in length per unit length) is known as
Modulus of elasticity
If an entire piece of material is only one crystal, its properties will vary with direction. That material is set to be
Anisotropic
If an entire piece of material is made up of small crystals that are randomly oriented and its properties are identical regardless of direction, the material is said to be
Isotropic
Temporary deformation of a material when stress is applied, which fully reverses when stress is removed, is also known as
Elastic deformation
Permanent deformation of a material when a stress is applied and then removed is also known as
Plastic deformation
A ________ phase diagram graphically illustrates the relationship between temperature, composition, and the phase present in a particular allo system
Equilibrium
An iron-carbon mixture with more than 2.11% carbon is commonly referred to as
Cast iron
Heating a piece of material to specific temperature range, holding at the temperature for a period of time, and cooling it slowly at a specific cooling rate describes what metal-working proces
Annealing
Annealling to remove strain hardening due to previous cold working and to restore ductility so that additional cold working on the product can be performed is called
Process annealing
The technique used to provide uniformity in grain size and composition throughout the thickness of steel prior to further processing is called
Normalizing
When some alloys are aged at room temperature or at a slightly elevated temperature, it increases the mechanical properties due to the precipitation of alloying elements. This procedure is called
Precipitation hardening
The degradation of a material, or deterioration of physical properties, due to a reaction with its environment describes
Corrosion
The most common type of corrosion, which is caused by a chemical or electrochemical reaction that deteriorates the entire exposed surface of the material, is referred to as
General corrosion
Corrosion that occurs under gaskets or seals, inside cracks or seams, or in spaces filled with deposits and under sludge piles is called
Crevice corrosian
Corrosion that occurs as a result of localized attack attack at or near the grain boundaries in a metal or alloy is called
Intergranular corrosion
The imperfection of crystals that are missing or have a few extra atoms is referred to as
Point defect
What the crystalline lattice is deformed in a spiral form, the dislocation is called
Screw dislocation
When the material is “cold worked” at room temperature, causing plastic deformation, it becomes harder to deform. This process is called
Strain hardening
A material that is plastically deformed (rolled, pressed, drawn, extruded, and so on) above it’s recrysttallization temperature is said to have been
Hot worked
