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Guide
- Most widely used Metal?
- Rockwell Hard- ness Test
- Brinell Hardness Test
Steel (Carbon Steels and cast irons)
the most widely used hardness test, and is similar to the Brinell test, with the hard- ness value again being determined by an indentation or penetration produced by a static load.
uses a hydraulic press to penetrate the metal.
- Tensile Testing Pull specimen apart till it breaks. It determines the failure of ductile materials in tension or compression below the elastic limit.
- How do you Iden- Weight, Shape ,Texture and Visual appearance tify Metals?
- Tempering 1.) Heat the steel carefully observe for color change
2.) Stop heating when the area you are treating reaches the necessary tempera- ture.
3.) Quench the steel
- Annealing is used to make a hardened workpiece soft again.
- Hardening 1.) Steel is heated till it turns into austenite
2.) Steel must be quenched (cooled) to form martensite.
- Coke is Coal baked at 1150 Celsius for 18 hours.
- Taconites Iron % 25- 30%
- Brass is a yellowish color ,it produces no sparks. it is slightly lighter then copper and resists water and corrosion.
Guide
70% copper/30% zinc
- Austenite is formed when pearlite is heated to a red heat, exists only in hot temperatures.
- Steel a strong, hard metal made of iron and carbon
- Hematite Iron Content %
70% iron
- Low carbon steel 0.02 -0.30% Carbon
- Medium Steel 0.30-0.60% Carbon
- High carbon steel 0.60 to 1.7% carbon
- Lime stone serves as a flux to remove impurities from metals.
- Martensite the structure of hardened steel, it consists of angular needle-like crystals.
- Pearlite the structure of soft steel
- Ferrite pure iron
- Cementite a carbide compound formed from carbon and iron
- Cold rolled steel it is recognized by its smooth grey surface and is produced by cleaning the scale from hot rolled billets and then drawing them through rollers or dies.
- Hot rolled steel is recognized by its black oxidized surface and is produced by drawing red hot billets through rollers,
- Elasticity is defined as the ability of a metal to regain its original shape after a deflecting force has been removed.
- Brittleness metals that shatter easily (most types of cast iron are )
- Cast iron Manu- facturing
Ore made into powder, iron content raised to 65%. Powder is mixed with clay to make pellets, pellets are covered with coal dust and baked. This makes a hard pellet easy for transportation.
Cupola furnace, uses layers of coke, cast iron and scarp iron, fuel is ignited, iron dropped into bottom of furnace filled into ladles then molded.
- Blast furnace steel shell lined with heat resistant brick
- Austenitic Stain- less steel
- Ferritic Stainless Steel
- Martensitic Stain- less Steel
chromium/nickel cant be hardened, great machine properties, corrosion resistant, cant be magnetic
Chromium (no nickel) resists corrosion- lacks strength-cannot be hardened
Chromium- can be hardened, not corrosion resistant
- AISI Code for designating carbon and alloy steels uses four-five digit numbers, the fist two number denote the type of steel, while the lasty 2 or 3 denote carbon content in hundredths of a percent.
