Metals Flashcards
______ employed for various engineering purposes and requirements
________ is the most popular metal in the field of engineering
ALL the metals have a _______
metals
iron
crystalline structure
________ is a mixture or compound of two or more elements, at least one of
which is metallic
______ enhances some properties, as required by engineering applications,
such as strength and hardness in comparison to pure metals
Classified into _________ and ________
An alloy
Alloying
solid solution and intermediate phase
__________
atoms of solvent element are
replaced in its unit cell by
dissolved element.
Substitutional solid solution
________ is an alloy in which one element is dissolved in another to form
a single-phase structure
In a solid solution, the solvent or base element is _______, and the dissolved
element can be either _________
Solid solutions can be __________ or ____________
Solid solution
metallic
metallic or nonmetal
Substitutional Solid Solution or Interstitial Solid Solution
_________ atoms
of dissolving element fit into
vacant spaces between base
metal atoms in the lattice
structure.
Interstitial solid solution -
There are usually limits to the solubility of one
element in another. When the amount of the dissolving element in the alloy
exceeds the solid solubility limit of the base metal, _________ fo______ is used to describe it because its
chemical composition is intermediate between the two pure elements. Its
crystalline structure is also different from those of the pure metals.
a second phase
intermediate phase
IMPORTANCE OF METALS
_________ – can be alloyed for high rigidity, strength, and
hardness
________ – capacity to absorb energy better than other classes of materials
________ – metals are conductors
___________ – conduct heat better than ceramics or polymers
____ – the price of steel is very competitive with other engineering materials
High stiffness and strength
Toughness
Good electrical conductivity
Good thermal conductivity
Cost
METALS USED IN MANUFACTURING PROCESS
_______ - starting form is a casting
_________ - the metal has been worked or can be worked
after casting
_________ - starting form is very small powders for
conversion into parts using powder metallurgy techniques
Cast Metal
Wrought Metal
Powdered Metal
CLASSIFICATION OF METALS
___________
These metals contain iron as main constituent
are classified as cast iron, wrought iron, and steel depending
upon ingredients and percentage of carbon content
____________
These metals practically do not contain iron
FERROUS METALS
NON-FERROUS METALS
_______ contains a higher percentage of carbon ranging from _______
________ is manufactured by melting of pig Its properties
1. It can be hardened by heating and sudden cooling, but it cannot be tempered.
2. It does not rust easily.
3. It is fusible.
4. It is hard and at the same time brittle.
Cast Iron
2 to 4.23
Cast Iron
CUPOLA.
Cast Iron (C.I.) Classification
1. ___________ - The carbon content is about ____ ad when fractured gives a
grey appearance. It is soft and readily melts. Its strength is weak and is used
for casting cylinders, pistons, manholes etc.
2. _________ - Its carbon content is ______. It contains carbon in
chemical form and on fracturing gives silver white luster. It is hard, not
workable on machines and is used for preparing pump liners, drawing dies
etc.,
3. ___________ its carbon content is 3.3%. It is produced by casting the
molten metal against a metal chiller to obtain a surface of white cast iron.
This is hard to a certain depth from the outer surface, which indicates the
white iron. The inner portion of the body is made up of grey iron which is soft.
It is used for manufacturing rail car wheels, dies, sprockets etc.
Grey Cast Iron
3%
White Cast Iron
2.0 to 2.5%.
Chilled Cast Iron
- ___________- Its carbon content is __. The composition of this is
so adjusted that it becomes malleable. It is done by extracting a portion of
carbon from cast iron. It has high field strength and used for manufacture of
automobile and railway equipment such as rail cars, crank shafts gear boxes
etc. - _________- It is obtained by melting cast-iron with wrought iron
scrap. The proportion of wrought-iron scrap is about _________ of cast-iron.
Malleable Cast Iron
2.3%
Toughened Cast Iron
1/4 to 1/7th
It is an almost pure iron. Its carbon content is 0.15%
Stages
_____________________
Properties
1. It is _____ at white stage of heat. It can be easily forged and welded.
2. It is ductile, malleable and tough.
3. Its melting point is ________
4. It is resistant to ________.
Wrought Iron
Refining-Puddling-Shingling-Rolling
soft
1500°C.
corrosion
__________ is defined as the iron alloy with a carbon content of up to ____%.
Types of steel include low carbon steel or mild steel, medium carbon
steel, and high carbon steel.
Steel
2.0
__________ 0.10 to 0.3% It can be easily hardened and
tempered
It is malleable and ductile
It can be forged and welded
It rusts easily
Specific gravity is ___
Sheets, Tin Plates
Low Carbon or Mild
7.8
________ 0.3 to 0.6% These steels have high strength,
toughness, hardness and stiffness
Boiler plates, Railway
tyres, pressing dies
Medium Carbon
________ 0.6 to 1.50% It can be easily hammered and tempered
Specific gravity is ___
It can be magnetize permanently
It is granular in structure
Springs, Hammers,
Drills, Chisel
High Carbon
7.9
Steel, to which elements other than carbon are added in sufficient quantity, in
order to obtain special properties, is known as _______.
Examples of alloy steels include chromium steel, cobalt steel, manganese steel,
tungsten steel, vanadium steel and Nickel steel.
Alloy Steel
__________ - Chromium up to ____
Vanadium up to _____
Highly ductile, can be easily
worked and welded
Used for locomotive springs,
pistons and bolts
Chromium Steel
0.9%,
0.15%
__________ Cobalt is added to high
carbon steel
Possesses magnetic
properties
Used for making permanent
magnet with strong
magnetic field
Cobalt Steel