CWB level 3 module 20
Compared to non metals, metals have - ANS1. High electric conductivity
2. High thermal conductivity
3. High particular gravity
4. Often ductile and may be fashioned
five. Metallic's bodily houses may be substantially motivated with the aid of it is alloying
materials.
In metals, electric and thermal conductivity .. - ANSParalell every different
Cu and Al are used as .. - ANSelectrical conductors
Gold and silver are used as .. - ANSelectrical contacts
Electrical conductivity helps for .. - ANSarc welding and resistance welding
Very excessive thermal conductivity makes .. - ANSarc welding tough and resistance welding
impossible bcz warmth is hastily eliminated from weld
Thermal conductivity of Cu - ANS394 W(m c) / 230 BTU
Electrical resistivity of Cu - ANS1.Seventy two x 10 ^ -8 ohm m
Thermal conductivity of Aluminum - ANS222 W(m c) /130 BTU
Electrical resistivity of Al - ANS2.83 x 10 ^ -eight ohm m
Thermal conductivity of Carbon metal - ANS46 W(m c) /26.8 BTU
Electrical resistivity of Carbon steel - ANS16.0 x 10 ^ -8 ohm m
Pure Cu - ANSCannot be seam / spot/ projection welded
Al - ANSCannot be spot / seam welded in skinny sections. High currents required
Carbon metal.. - ANSEasily welded by all resistance welding methods
Two ores of iron - ANSMagnetite (Fe3 O4) & Hematite ( Fe2O3)
Ore of Al - ANSBauxite ( Al2 O3)
, Iron is extracted with the aid of - ANSsmelting in a blast furnace by using blowing warm air over
coke to produce carbon monoxide, which removes O2 from the ore, leaving the iron as a liquid
metallic.
Al from Bauxite can not be extracted with the aid of.. - ANSheating method
Bauxite is extracted by . - ANSelectrical method
Plot of loose energy of oxides - ANSEllingham diagram
Large unfastened energy suggests a - ANSvery strong oxide
Gold ore is stable at - ANSroom temperature and doesn't corrode
Most of the metals are handiest strong at - ANShigh temperatures and a reducing agent is used
to lower O2 capability
Rate of oxidation increases with.. - ANSincrease in temp.
Stability of oxide decreases with .. - ANSincrease in temp.
Gold may be - ANScold welded
diploma of safety required while welding will depend on - ANSreactivity of metals .,ie, price of
oxidation and the stableness of oxide.
Lead can be fusion welded with - ANSno sheilding
Melting temp of lead - ANS327 C
Shielding required for lead - ANSMinimal, gas flame is ok
Melting temp of Cu - ANS1083 C
Shielding required for Cu - ANSFlux or inert fuel
Melting temp of Al - ANS660 C
Shielding required for Al - ANSInert fuel is preffered
Melting temp of Steel - ANS1350 C
Shielding required for Steel - ANSFlux, inert gasoline or CO2
Compared to non metals, metals have - ANS1. High electric conductivity
2. High thermal conductivity
3. High particular gravity
4. Often ductile and may be fashioned
five. Metallic's bodily houses may be substantially motivated with the aid of it is alloying
materials.
In metals, electric and thermal conductivity .. - ANSParalell every different
Cu and Al are used as .. - ANSelectrical conductors
Gold and silver are used as .. - ANSelectrical contacts
Electrical conductivity helps for .. - ANSarc welding and resistance welding
Very excessive thermal conductivity makes .. - ANSarc welding tough and resistance welding
impossible bcz warmth is hastily eliminated from weld
Thermal conductivity of Cu - ANS394 W(m c) / 230 BTU
Electrical resistivity of Cu - ANS1.Seventy two x 10 ^ -8 ohm m
Thermal conductivity of Aluminum - ANS222 W(m c) /130 BTU
Electrical resistivity of Al - ANS2.83 x 10 ^ -eight ohm m
Thermal conductivity of Carbon metal - ANS46 W(m c) /26.8 BTU
Electrical resistivity of Carbon steel - ANS16.0 x 10 ^ -8 ohm m
Pure Cu - ANSCannot be seam / spot/ projection welded
Al - ANSCannot be spot / seam welded in skinny sections. High currents required
Carbon metal.. - ANSEasily welded by all resistance welding methods
Two ores of iron - ANSMagnetite (Fe3 O4) & Hematite ( Fe2O3)
Ore of Al - ANSBauxite ( Al2 O3)
, Iron is extracted with the aid of - ANSsmelting in a blast furnace by using blowing warm air over
coke to produce carbon monoxide, which removes O2 from the ore, leaving the iron as a liquid
metallic.
Al from Bauxite can not be extracted with the aid of.. - ANSheating method
Bauxite is extracted by . - ANSelectrical method
Plot of loose energy of oxides - ANSEllingham diagram
Large unfastened energy suggests a - ANSvery strong oxide
Gold ore is stable at - ANSroom temperature and doesn't corrode
Most of the metals are handiest strong at - ANShigh temperatures and a reducing agent is used
to lower O2 capability
Rate of oxidation increases with.. - ANSincrease in temp.
Stability of oxide decreases with .. - ANSincrease in temp.
Gold may be - ANScold welded
diploma of safety required while welding will depend on - ANSreactivity of metals .,ie, price of
oxidation and the stableness of oxide.
Lead can be fusion welded with - ANSno sheilding
Melting temp of lead - ANS327 C
Shielding required for lead - ANSMinimal, gas flame is ok
Melting temp of Cu - ANS1083 C
Shielding required for Cu - ANSFlux or inert fuel
Melting temp of Al - ANS660 C
Shielding required for Al - ANSInert fuel is preffered
Melting temp of Steel - ANS1350 C
Shielding required for Steel - ANSFlux, inert gasoline or CO2
