Types of Alloys and Iron Alloys
ALLOYS
Mixing 2 or more metals with specific properties and it consists of metal and other nonmetal such as carbon
Table of Contents
How to prepare Alloys?
Preparation of Alloys:
1)by melting: Melting of the metals together then left them to cool gradually
2)by electro-deposition Electro deposition of 2 metals or more at the same time
Ex: electroplating of iron handles with brass alloy (Yellow copper alloy) (Cu + Zn)
-On hammering a layer of metal atoms can move over the other that makes pure iron malleable and ductile
Types of Alloys ?
Interstitial alloy
How to prepare Interstitial
by introducing smaller atomic size element in space of pure metal to prevent the movement of metal layers when hammering
Properties Interstitial alloy
1-increase the hardness
2-change the physical properties like ductility ,elec. conductivity ,malleability and magnetic property
Examples:steel (Iron carbon) alloy
Substitutional alloys
How to prepare Substitutional alloy ?
by substitution some atoms of the pure metal by atoms of other metal
Which has:
1-the same crystal lattices
2-the same chemical properties
3-the same atomic radius
Examples:
Iron-Nickel alloy(ferronickle)
copper gold alloy
Iron chromium alloy( ferrochromium )stainless steel alloy
Inter-metallic alloys
Formed by chemical combination between elements forming chemical compound with chemical formula disobey the rules of valence
-occurs between elements metals found in different groups in periodic table
Examples:
- Aluminium-Nickel alloy ,Aulminium coppe (called Dueralumin)
- Iron Carbon Fe3C
- Lead gold alloy Au2Pb
Quiz about: about alloys and their preparation:
1-What is an alloy?
a) Pure metal
b) Mixture of metals
c) Non-metallic compound
d) Noble gas
2- Which of the following is NOT a common method for preparing alloys?
a) Fusion
b) Electroplating
c) Cementation
d) Powder Metallurgy
3-Brass is an alloy of:
- a) Copper and Zinc
- b) Iron and Carbon
- c) Aluminum and Silicon
- d) Gold and Silver
4- What is the purpose of alloying metals?
a) To increase conductivity
b) To decrease hardness
c) To enhance strength and other properties
d) To reduce density
5-Stainless steel is an alloy that contains:
a) Iron and Aluminum
b) Iron and Nickel
c) Iron and Chromium
d) Iron and Copper
6- Which process involves heating a metal to a high temperature and then cooling it slowly to improve its properties?
a) Quenching
b) Annealing
c) Tempering
d) Hardening
7-Bronze is an alloy of:
a) Copper and Tin
b) Copper and Zinc
c) Iron and Carbon
d) Aluminum and Silicon
8-Which method involves coating a metal with a layer of another metal through electrolysis?
a) Galvanization
b) Cementation
c) Alloying
d) Sintering
9-Which alloy is known for its high strength and corrosion resistance, making it suitable for aerospace applications?
a) Brass
b) Bronze
c) Titanium alloy
d) Pewter
Answers:
- b) Mixture of metals
- b) Electroplating
- a) Copper and Zinc
- c) To enhance strength and other properties
- c) Iron and Chromium
- b) Annealing
- a) Copper and Tin
- a) Galvanization
- a) Lead
- c) Titanium alloy
Quiz 2
1-Which alloy is commonly used as a structural material in aircraft and aerospace applications due to its high strength-to-weight ratio?
a) Brass
b) Bronze
c) Stainless steel
d) Titanium alloy
2-The alloy “Nichrome” is used for making:
a) Coins
b) Electrical resistance heating elements
c) Aircraft parts
d) Cutlery
3-What type of alloy is formed by combining a metal with a non-metal?
a) Intermetallic alloy
b) Ternary alloy
c) Amorphous alloy
d) Composite alloy
4-Which alloy is composed of iron and carbon, with carbon content typically ranging from 0.2% to 2.1%?
a) Stainless steel
b) Brass
c) Bronze
d) Steel
5-What is the primary alloying element in bronze?
a) Zinc
b) Tin
c) Nickel
d) Chromium
6-Which process involves heating an alloy to a high temperature and then cooling it rapidly to increase its hardness?
a) Quenching
b) Annealing
c) Tempering
d) Hardening
Answers:
- d) Titanium alloy
- b) Electrical resistance heating elements
- c) Amorphous alloy
- d) Steel
- b) Tin
- a) Quenching
Quz3 : mention the 3 types of alloys
Alloys can be broadly classified into three main types:
Substitutional Alloys:
In substitutional alloys, atoms of the components replace each other in the crystal lattice structure.
Examples include brass (copper and zinc) and bronze (copper and tin).
Interstitial Alloys:
In interstitial alloys, smaller atoms of one component fit into the spaces between the larger atoms of the other component in the crystal lattice.
Steel is a common example of an interstitial alloy, where carbon atoms fit into the spaces between iron atoms.
Intermetallic Compounds:
Intermetallic compounds are alloys where the components combine in fixed stoichiometric ratios to form distinct compounds.
An example is the intermetallic alloy formed by combining aluminum and nickel to create the compound NiAl.
Each type of alloy has its own set of properties and applications, and the choice of alloy type depends on the desired characteristics for a particular use case.
Quiz 4
Here’s a quiz to test your knowledge about the three types of alloys: substitutional alloys, interstitial alloys, and intermetallic compounds.
1-Brass is an example of which type of alloy?
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Composite alloy
2-In which type of alloy do smaller atoms fit into the spaces between the larger atoms in the crystal lattice?
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Ternary alloy
3-Steel is an example of which type of alloy?
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Binary alloy
4-What is a characteristic feature of intermetallic compounds?
a) Atoms replace each other in the crystal lattice
b) Smaller atoms fit into spaces between larger atoms
c) Components combine in fixed stoichiometric ratios
d) Components form an amorphous structure
5-Which alloy type involves atoms of the components replacing each other in the crystal lattice structure?
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Ternary alloy
6-Nickel and Aluminum combining in a fixed ratio to form NiAl is an example of a:
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Composite alloy
7-What type of alloy commonly consists of copper and tin?
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Ternary alloy
8-Which alloy type is exemplified by the combination of carbon atoms fitting into spaces between iron atoms?
a) Substitutional alloy
b) Interstitial alloy
c) Intermetallic compound
d) Binary alloy
9-Ternary alloys involve the combination of how many components?
a) One
b) Two
c) Three
d) Four
10-What property makes steel, an interstitial alloy, different from pure iron?
a) Increased ductility
b) Enhanced hardness
c) Higher electrical conductivity
d) Lower melting point
Answers:
- a) Substitutional alloy
- b) Interstitial alloy
- b) Interstitial alloy
- c) Components combine in fixed stoichiometric ratios
- a) Substitutional alloy
- c) Intermetallic compound
- a) Substitutional alloy
- b) Interstitial alloy
- c) Three
- b) Enhanced hardness