What is the importance of aluminium having a high melting point, being malleable and a good conductor of heat?
Answers
Answer:
The melting point of a substance is the temperature at which it transforms from a solid to a liquid state. Metals show a high melting point as they exist in a crystalline solid form. High melting point metals have strong intermolecular forces between atoms. Electrostatic attraction forces between metal ions and free electrons create strong metallic bonds with stronger bonds resulting in higher melting temperatures.
Refractory Metals
There are two accepted definitions for refractory metals. One states a metal must have a melting point above 2200 °C, whilst the other states all metals with a melting point above 1850 °C are considered refractory metals. Using the broader definition, the following 14 metals are classified as refractory metals.
Metal
Melting Point
Applications
Tungsten (W)
3420 °C
Light bulbs filaments, welding electrodes, furnaces heating elements
Rhenium (Re)
3180 °C
Jet engine parts, alloying, oven filaments, x-ray machines
Tantalum (Ta)
2966 °C
Engine turbine blades, medical devices, military, semconductors
Molybdenum (Mo)
2620 °C
Coatings, solar cells, tool, and high-speed steels
Niobium (Nb)
2468 °C
Superconductors, steel alloying, tool steels, sodium-vapor lamps
Chromium (Cr)
1907 °C
Alloying, plating, catalyst
Hafnium (Hf)
2227 °C
Nuclear reactor control rods, alloying, microprocessors
Iridium (Ir)
2454 °C
Hardening agent, alloying (especially with osmium), pen tips, compass bearings
Osmium (Os)
3050 °C
Alloying, needles, pen tips
Rhodium (Rh)
1960 °C
Alloying, catalyst, jewellery
Ruthenium (Ru)
2310 °C
Solar cells, alloying (especially with platinum and palladium), jewellery
Titanium (Ti)
1668 °C
Alloying, aircraft, ships, propellor shafts, heat exchangers
Vanadium (V)
1910 °C
Alloying (especially with steel and titanium)
Zirconium (Zr)
1855 °C
Nuclear reactors, magnets (alloyed with niobium), chemical industry