Molybdenum( Mo )
Originally molybdenum was confused with graphite and lead ore, and was not prepared till 1782 by Hjelm in the impure state.
Molybdenum is a refractory metal typically used in high temperature applications. Its ability to withstand high temperatures and maintain strength under these conditions are responsible for the fact that molybdenum finds most of its application at elevated temperatures. In fact, it can work at temperatures above 1100°C (in non-oxidising conditions), which is higher than steels and nickel-based superalloys.
Molybdenum metal is used in:
· Alloying agent – contributing hardenability, toughness to quenched/tempered steels. It also improves the strength of steels at high temperatures (red-hardness).
· In nickel-based alloys (such as Hastelloys®) and stainless steels it imparts heat-resistance and corrosion-resistance to chemical solutions.
· Electrodes for electrically heated glass furnaces and forehearths.
· Nuclear energy applications, as missile and aircraft parts (where high temperature resistance is vital).
· As a catalyst in the refining of petroleum.
· As a filament material in electronic/electrical applications.
· As a support members in radio and light bulbs.
· Arc resistant electric contacts.
· Thermocouple sheaths
· Flame- and corrosion-resistant coatings for other metals