Materials: Metals

Materials: Metals

Ferrous: 
-Ferrous metals are magnetic. 
- Contains iron, produced and used in larger quantities, make up more than half of all metal consumption.

VS

Non Ferrous: 
-Non Ferrous metals are non-magnetic (exceptions of cobalt and nickel)

Alloy: 
-Alloys are hybrids of different metallic elements combined to enhance properties and reduce costs. 
-Steel is a good example of an alloy metal. 

Wrought iron/ Cast iron:
-Low cost structural material, heavy & soft that is relatively easy to form hot or cold. ---    ---Wrought iron contains less than 0.2% carbon and largely replaced by steel, traditionally used in architectural metalwork and fencing, useful in construction industry, high thermal conductivity, cast iron contains between 2-4% carbon.
-low to moderate costs.

Steel: 
-This is the most common metal. It is used for many industrial and domestic applications. 
-Carbon steel: low, medium, or high carbon content ranging.
-Low alloy steels are made up of iron, carbon and up to approx. 10% of other metals
-Stainless steels contain iron, less than 1% carbon, 10% chromium or more and other alloys and is resistant to errosion.


-4 main types of steel include: 
austenitic - ductile, strong, non-magnetic 
ferritic - less strong, magnetic, generally used indoors 
martensitic - hardest but least corrosion resistant
precipitation - hardens to high strength with moderate resistance.

- More than 3/4 steel production is carbon steel. Stainless steel are used mainly in decoration and functional applications.
-Cost fluctuates



Aluminium Alloys:
- Lightweight and conductive metal that is non toxic 
- Used in a range of decorative and functional applications. 
- Pure aluminum is ductile and has good strength to weight
- Used in a wide range of applications: packaging, drink cans, cooking equipment, planes, trains, ships, construction.
- Cost moderate to high.

Magnesium Alloys:
Better strength to weight than aluminum but more expensive. Often alloyed with aluminium, silicon, and zinc. Explosive especially in powder form. Bright flame used in pyrotechnics and flares. many applications are the same as aluminium. costs moderate to high.

Titanium Alloys:
- Alternative to aluminium and magnesium, limited to applications that demand high strength to weight and superior corrosion resistance. 
-Naturally occurring oxide that forms on the surface. 
-High costs

Zinc Alloys:
- They exhibit high resistance to corrosion 
- Low viscosity and a relatively low melting point. suited for casting, and forming small, bulk, sheet, complex, and intricate shapes. 
- Resistant to atmospheric corrosion. 
- Moderate costs.

Copper Alloys:
-Copper alloys are ductile, have a low melting point and are easy to form. 
-Copper develops a protective and decorative patina on its surface, changes color over time. efficient thermal and electrical conductor. considered hygienic, many bacteria neutralize when they come in contact with it. Brass is an alloy of copper and up to 40% tin. used for its conductive properties, electrical cables, heating elements. cost low to moderate.

Nickel Alloys:
- Mainly used for electroforming, electroplating and as an alloy in stainless steel. 
- Good resistance to oxidization and corrosion. 
- Moderate to high cost.

Lead and Tin Alloys:
- lead and tin alloys and pewter have low melting points. 
- efficient for casting, can produce high detail. 
- "white metals" are used in casting applications and often plated with another metal. 
- cost low

Precious Metals:
- silver is bright and highly reflective, has to be polished and or colored over often to keep its brightness. not an effective conductor. silver ions have antimicrobial properties. 
- gold is very soft and malleable and ductile, can be beaten into thin sheets, known as gold leaf. 
Pure gold is yellow, different colors are produced by varying the alloy content. 
Red or pink gold contains copper, white gold contains platinum, silver or zinc, purple gold contains a precise measure of aluminium, blue and black are also possible. the purity of gold is measured in carats, 24 is pure, 18 ct is 75%. 
-Platinum is the most rare and precious and most expensive, its hard, durable, ductile, resistant to corrosion by abrasion, oxygen and many chemicals. it is a good conductor and catalyst. costs high to very high.