Aug 7 2013
Topics Covered
Introduction
Chemical Properties
Physical Properties
Mechanical Properties
Thermal Properties
Applications
Introduction
Tellurium is a chemical element with Te as its symbol. It belongs to group 16, periodic number 5 of the periodic table. Its atomic number is 52.
Tellurium is a silvery-white semi-metallic element that is crystalline and brittle. It remains stable in water or hydrochloric acid, but will dissolve in nitric acid. It is a semiconductor and is often doped with tin, gold, silver, or copper.
Tellurium is obtained from the ores calaverite, krennerite, and sylvanite. It can also be obtained as a byproduct of mining and refining copper. It is produced mainly in USA, Canada, Japan, and Peru.
Chemical Properties
The chemical properties of tellurium are provided in the table below.
Chemical Data |
CAS number |
13494-80-9 |
Thermal neutron cross section |
4.7 barns/atom |
Ionic radius |
0.560 Å |
Electronegativity |
2.1 |
X-ray absorption edge |
0.38972 Å |
Electrochemical equivalent |
0.99 g/A/h |
Physical Properties
The following table discusses the physical properties of tellurium.
Properties |
Metric |
Imperial |
Density |
6.23 g/cm3 |
0.225 lb/in3 |
Melting point |
450°C |
842°F |
Boiling point |
1390°C |
2534°F |
Mechanical Properties
The mechanical properties of tellurium are tabulated below.
Properties |
Metric |
Imperial |
Tensile strength |
11MPa |
1600 psi |
Poisson’s ratio |
0.33 |
0.33 |
Modulus of elasticity |
40 GPa |
5800 ksi |
Shear modulus |
15.16 GPa |
2199 ksi |
Hardness, Brinell |
25 |
25 |
Thermal Properties
The thermal properties of tellurium are tabulated below.
Properties |
Metric |
Imperial |
Thermal expansion co-efficient (@20-100°C/68-212°F) |
16.8 µm/m°C |
9.33 µin/in°F |
Thermal conductivity |
1.97 W/mK |
13.7 BTU in/hr.ft².°F |
Applications
The following are the application areas of tellurium:
-
As an additive to steel
-
Alloyed to copper, aluminum, lead or tin
-
As an additive to lead to enhance its strength, durability, and resistance to corrosion
-
For ceramics, blasting caps, cast iron, solar panels, and chalcogenide glasses
-
As an additive to rubber to speed up the curing process, reduce the susceptibility of the rubber to ageing, and to increase its resistance to oil.