Production Of Metals Flashcards
Ingredients in a blast furnace
Iron ore, coke, limestone
Coke is….
Refined coal.
Blows oxygen rich air to remove carbon as CO2 that bubbles out (blast furnace)
Tuyeres
Pig iron
4-5 percent carbon
Raw ingredient
Cupola furnace
Charged with pig iron and scrap cast iron. (Makes cast iron)
Main hardening agent in steel
Carbon
Induction furnace
Makes cast iron
Uses electricity instead of fire
Basic oxygen steel making furnace (bos)
Loaded with 70-80 percent scrap steel and molten pig iron
Electric arc furnace
Graphite electrodes
Controlled environment
Highest quality steel and alloys
Carefully selected scraps
Tundish
A reservoir with a drain
(Continuous casting process)
Hot rolled steel
Formed while hot
Mill scale
Rounded corners
Greater ductility
Less exact dimensions
Cold rolled
Formed below lower critical temp
Shiny and smooth
Sharp corners
Greater strength
Precise dimensions
Carbon content in
Pig iron…..
Cast iron….
Steel…
Pig iron: 4-5 %
Cast iron: 2-4.5%
Steel max: 2%
Grey cast iron
2.5-4%
Brittle
Extreme hardness
Absorbs vibration
Excellent wear resistance
White cast iron
Grey cast iron poured into a chilled mold
Harder and more brittle than grey
Better wear resistance than grey cast
Malleable cast iron
Annealed white cast iron
Has a small amount of ductility
(Plumbing fittings)
Ductile cast iron
Highest strength and ductility of cast irons
Alloyed with rare earth elements and manganese
(Valves and crankshafts)
0.05 - 0.30 carbon content
Low carbon
0.30 - 0.45 carbon content
Medium carbon
0.45. - 0.75 carbon content
High carbon
0.75 - 1.50 carbon content
Very high carbon
Killed steel
Fully deoxidized
Highest quality
Semi killed
Some deoxidizers added
Medium quality
Rimmed
No deoxidizers added
Lowest quality
Capped
No deoxidizers added
Cap added to slow cooling
Slightly better than rimmed
With the basic oxygen steel making process what is the purpose of blowing in oxygen
To combine with the carbon
What is the continuous casting process
Where molten metal is solidified into billets, blooms, blanks, rounds or slabs
From a ladle to a tundish then to continuous casting
What is the carbon content for cast irons
2 - 4.5%
Highest strength and ductility
Crankshafts and valves
Alloyed with rare earth elements and manganese (which cast iron)
Ductile or nodular cast iron
Used as a flux in the blast furnace to help remove impurities
Limestone
Pig iron is refined to produce either …
Cast iron or steel
Process where molten steel is solidified into billets, blooms, blanks, rounds or slabs…
Continuous casting
(Improve yield, quality, productivity and cost efficiency)
Based on the deoxidization process, what are the four classes of steel
- Rimmed
- Capped
- Semi killed
- Killed
Which metal leaves the steel making furnace and is poured into a mould that is in the shape of the final product
Cast iron
4 types of cast iron
- Grey
- White
- Malleable
- Ductile or nodular
Why is limestone added to the blast furnace
To act as a flux to remove impurities
Engine blocks, tools, machinery and fly wheels are made from which cast iron
Grey
Two main ing in steel are
Iron and carbon
Level of quality in deoxidization process
- Killed - fully deoxidized
- Semi killed - some deoxidizers added
- Capped - no deoxidizers added cap added to slow cooling
- Rimmed - no deoxidizers
Which cast iron is crushing and grinding equipment
White cast iron
Better wear resistant more brittle than gray, rapidly cooled not weldable
Which cast iron is annealed, rounded carbon particles, greater ductility ex plumbing fittings
Malleable cast iron
Which steel making process is commonly used for making high quality alloy and tool steels
An electric arc furnace
The first step in separating the iron from the oxygen in the naturally occurring iron ore
Blast furnace
Carbon content in coke
98 %
Molten metal starts to cool and gets a thin shell of solidified metal in outside the middle is still molten and is now called
A strand
Why is continuous casting preferred to stationary moulds
Increase control through automation
Lower cost
Improve yield
Quality productivity
5 types of moulds
Billets
Blooms
Blanks
Rounds
Slabs
Which type of cast iron has extreme hardness due to rapid cooling
White cast iron
Which type of cast iron has the highest strength and can be used for making valves
Ductile or nodular cast iron
Which type of cast iron undergoes an annealing process
Malleable cast iron
What is the carbon content range for steels
Less than 2 %
What is rimmed steel used for
Core wire, electrodes, bar stock, plate and some structural steel
