Jul 11 2013
Topics Covered
Introduction
Chemical Properties
Physical Properties
Mechanical Properties
Thermal Properties
Applications
Introduction
Iron is a chemical element with Fe as its symbol. It belongs to group 8, periodic number 4 of the periodic table. Its atomic number is 26.
Iron makes up 5% of the Earth's crust and is one of the most abundantly available metals. It is primarily obtained from the minerals hematite and magnetite. It can also be obtained from taconite, limonite, and siderite. Iron is the most used of all the metals.
Iron is also found in meat, potatoes and vegetables and is essential for animals and humans. It is an essential part of hemoglobin.
Iron metal is greyish in appearance, and is very ductile and malleable. It begins to rust in damp air and at elevated temperatures, but not in dry air. It dissolves readily in dilute acids, and is chemically active.
The main mining areas for iron are China, Australia, Brazil, Russia, and Ukraine.
Chemical Properties
The chemical properties of iron are provided in the table below.
|
Chemical Data |
|
CAS number |
7439-89-6 |
|
Thermal neutron cross section |
2.53 barns/atom |
|
Electrode potential |
-0.0400 V |
|
Ionic radius |
0.640 Å |
|
Electronegativity |
1.83 |
|
X-ray absorption edge |
1.743 Å |
|
Electrochemical equivalent |
0.695 g/A/h |
Physical Properties
The following table discusses the physical properties of iron.
|
Properties |
Metric |
Imperial |
|
Density |
7.87 g/cm3 |
0.284 lb/in3 |
|
Melting point |
1536 °C |
2797°F |
|
Boiling point |
2861 °C |
5182°F |
Mechanical Properties
The mechanical properties of iron are tabulated below.
|
Properties |
Metric |
Imperial |
|
Tensile strength at break |
540 MPa |
78300 psi |
|
Yield strength |
50 MPa |
7250 psi |
|
Poisson’s ratio |
0.291 |
0.291 |
|
Modulus of elasticity |
200 GPa |
29000 ksi |
|
Shear modulus |
77.5 GPa |
11200 ksi |
|
Hardness, Brinell |
146 |
146 |
|
Hardness, Vickers |
150 |
150 |
|
Hardness, Rockwell A |
49 |
49 |
|
Hardness, Rockwell B |
79 |
79 |
Thermal Properties
The thermal properties of iron are tabulated below.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@20-100°C/68-212°F) |
12.2 µm/m°C |
6.78 µin/in°F |
|
Thermal conductivity |
76.2 W/mK |
529 BTU in/hr.ft².°F |
Applications
Iron is used in numerous sectors such as electronics, manufacturing, automotive, and construction and building.
The following are the application areas of iron:
-
As the primary constituent of ferrous metals/alloys and steels
-
Alloyed with carbon, nickel, chromium and various other elements to form cast iron or steel
-
In magnets
-
In fabricated metal products
-
In industrial machinery
-
In transportation equipment
-
In instruments
-
In toys and sport goods