Properties and Uses of Common Metals
Copper
It exists in pure form in nature and in minerals such as sulfides and oxides. Copper is an excellent electrical and thermal conductor. It is tough, wear-resistant, very ductile, and malleable.
Alloys:
- Bronze (copper + tin + others)
- Brass (copper + zinc + others)
- Cuproaluminum
- Alpaca (copper + nickel + zinc)
- Copper-nickel
Applications:
- Cables
- Refrigerators
- Radiators
- Tin solder joints
- Naval applications
- Agriculture (fungicides and insecticides)
- Pigments
- Brass (resistant to atmospheric and marine corrosion)
Aluminum
Abundant in nature, aluminum is extracted from bauxite. It is a light metal with good electrical and thermal conductivity, resistance to atmospheric corrosion, ductility, and malleability.
Alloys:
- Brass and aluminum
- Aluminum-magnesium (high resistance to corrosion from fresh water and alkalis, used in shipbuilding and vehicle bodies)
- Alkaline
- Zamak (zinc + copper + aluminum + magnesium, used in automobiles)
Applications:
- Aviation
- Car bodies
- Boat hulls
Tin
Tin is found in the Earth’s crust, primarily as tin oxide cassiterite. It is heavy, resistant to atmospheric corrosion, malleable, and ductile.
Alloys & Applications:
- Tin plating protects steel from rusting in food and beverage containers.
Zinc
Zinc is quite abundant in the Earth’s crust and is extracted from calamine and sphalerite (Blenda). It is malleable, somewhat brittle, and resistant to corrosion in air.
Alloys:
- Brass
- Nickel silver
- Bronze
- Zamak
Applications:
- Roofing layers
- Gutters
- Galvanized steel (coated steel parts to protect them from corrosion)
- Chlorides (sunscreens and cosmetics)
- Sulfides (dyes)
- Oxides (glues and paints)
Lead
Lead is rarely found in its elemental state, usually occurring as Galena. It is a heavy metal with good electrical conductivity and castability.
Alloys and Applications:
- Radiation protection from X-rays
- Protective coatings
- Toy soldiers
Nickel
Nickel is found in nature as sulfides and arsenides, such as niccolite. It is tough, hard, malleable, ductile, has high strength and wear resistance, is magnetic, resistant to oxidation and corrosion, and a good conductor.
Alloys:
- Steel and chrome
- Nickel bronze
- Monel (copper + nickel)
Applications:
- Surgical and laboratory equipment
- Nickel plating
- Stainless steels
Chrome
Chrome is obtained from chromite and is hard, brittle, and resistant to corrosion.
Applications:
- Chrome paint
- Antioxidants
- Catalysts
- Tanning leather
- Corundum (aluminum ions are replaced by chromium to be used in ruby lasers)
Titanium
Titanium is found in igneous rocks and all plant and animal organisms. It is extracted from rutile and is abundant. It requires prior refining. It has a melting point of 1675 ºC, is paramagnetic, corrosion-resistant, refractory, has low thermal and electrical conductivity, allows chemical milling, is malleable, ductile, tough, weldable.
Noble Metals
Noble metals are chemically inert.
Gold
Gold is a soft, heavy metal, limited in nature, unlikely to corrode or rust, and a good conductor of heat and electricity. It is malleable and ductile.
Applications:
- Jewelry
- Electronics
- Dental implants
- Coinage
Silver
Silver is rather scarce and harder than gold. It does not rust easily and has excellent electrical and thermal conductivity. It is used in silver solder rods.
Applications:
- Usually alloyed with one or more metals for dental use
- Engine bearings and pistons
Platinum
Platinum is soft, ductile, malleable, and heavy.
Applications:
- Jewelry
- Monetary reserves
- Artificial implants
- Electrical conductors
- Sensors