METALS

• Is metal have lower electronegativities?

  Yes.
• are metals good reducing agents?

  yes
• is the melting point of metals high or low?

  yes
• do metals conduct electricity well?

  true
• metal is shiny, malleable, ductile, and has a high density.?

  true
• Classification of metals

  • ferrous
  • non-ferrous
• ferrous are made up of

  • steel
  • cast iron
• steels have

  • low alloy
  • high alloy
• high alloys has

  • stainless teel
  • tool steel
• Plain carbon steels - very low content of

  alloying elements ans small amounts of

  manganese.
• Most abundant grade of steel is low

  carbon steel - greatest quantity

  produced; least expensive.
• Low carbon steel is responsive to heat treatment?

  false
• low carbon steel has good machinability?


  true
• Medium Carbon content in the range of 0.3% to

  0.6%
• medium carbon steel can be heat treated?

  true
• Medium Carbon Steel - most often used in tempered condition.
• Medium carbon steels - have low

  hardenability
• High carbon steels - carbon content of

  0.6% - 1.4%
• High Carbon Steel - Hardest and least ductile
• High Carbon Steel - Used in hardened and tempered

  condition
• Stainless steels - a group of steels that

  contain at least 11% Cr, exhibits

  extraordinary corrosion resistance due

  to formation of a very thin layer of Cr2O3

  on the surface.
• Manganese - strength and hardness; decrease ductility and weldability; affects

  hardenability of steel
• Silicon - one of the principal deoxidizers used in steel making; in low-carbon steels,

  silicon is generally detrimental to surface quality
• cast iron has low melting point?

  true
• Types of cast iron: grey, white, nodular,

  malleable and compacted graphite
• Grey cast iron - contains graphite in the

  form of flakes
• Casting shrinkage is low in grey?

  true
• Nodular or Ductile Iron - Normally a pearlite matrix
• Copper - is one of the earliest metals

  discovered by man
• The second largest use of Cu is probably coins
• copper alloys

  • brass
  • bronze
  • beryllium
• Cast alloys are used in injection molds
• Aluminum - is a light metal (ρ = 2.7 g/cc);

  is easily machinable; has wide variety of

  surface finishes; good electrical and

  thermal conductivities; highly reflective

  to heat and light
• Brass - is the most common alloy of Cu -

  it’s an alloy with Zn
• Brass - is frequently used to make musical

  instruments
• Copper alloys containing tin, lead,

  aluminum, silicon and nickel are

  classified as bronzes
• bronze - can be

  cast, hot worked and cold worked
• Titanium - can also be cast using a vacuum furnace
• Nickel - is a high-density, high-strength

  metal with goof ductility and excellent

  corrosion resistance and high

  temperature properties
• Magnesium - lightest among commonly

  used metals