Conducting Material and Magenatic Material - PPT, Engineering, Semester Notes | EduRev

Created by: ANJU SANTHI

: Conducting Material and Magenatic Material - PPT, Engineering, Semester Notes | EduRev

 Page 1


AJITH VIJAYAN
Page 2


AJITH VIJAYAN
? Most important properties – thermal and 
electrical conductivity
? Silver has highest electrical conductivity, 
next is copper
? Conductivity of Cu is 5-10% less than silver.
? Supply of Cu is not abundant, hence Al which 
is light and has high conductivity is used 
commonly.
? Resistivity at 0°C & 20°C, µ ohm-cm
? Silver -1.51/1.629 
? Copper-1.589/1.724
? Al – 2.62/2.87
? Gold – 2.22/2.36
23-Jan-15
2 AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
Page 3


AJITH VIJAYAN
? Most important properties – thermal and 
electrical conductivity
? Silver has highest electrical conductivity, 
next is copper
? Conductivity of Cu is 5-10% less than silver.
? Supply of Cu is not abundant, hence Al which 
is light and has high conductivity is used 
commonly.
? Resistivity at 0°C & 20°C, µ ohm-cm
? Silver -1.51/1.629 
? Copper-1.589/1.724
? Al – 2.62/2.87
? Gold – 2.22/2.36
23-Jan-15
2 AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
? Temperature : Electrical resistance of most 
metals increases with increase in 
temperature and that of semiconductors and 
electrolytes decreases with increase of 
temperature.
? Alloying : Solid solution has a less regular 
structure than pure metal. The electrical 
conductivity of solid solution alloy decreases 
rapidly with increased alloy content. i.e
addition of small amount of impurities leads 
to increase in resistivity. Brass(63% Cu & 40% 
Zn) has a resistivity of 9µ O-cm where as Cu-
1.6 µ O-cm and Zn-6 µ O-cm 
23-Jan-15 3 AJITH VIJAYAN, EEE DEPT, GEC WAYANAD
Page 4


AJITH VIJAYAN
? Most important properties – thermal and 
electrical conductivity
? Silver has highest electrical conductivity, 
next is copper
? Conductivity of Cu is 5-10% less than silver.
? Supply of Cu is not abundant, hence Al which 
is light and has high conductivity is used 
commonly.
? Resistivity at 0°C & 20°C, µ ohm-cm
? Silver -1.51/1.629 
? Copper-1.589/1.724
? Al – 2.62/2.87
? Gold – 2.22/2.36
23-Jan-15
2 AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
? Temperature : Electrical resistance of most 
metals increases with increase in 
temperature and that of semiconductors and 
electrolytes decreases with increase of 
temperature.
? Alloying : Solid solution has a less regular 
structure than pure metal. The electrical 
conductivity of solid solution alloy decreases 
rapidly with increased alloy content. i.e
addition of small amount of impurities leads 
to increase in resistivity. Brass(63% Cu & 40% 
Zn) has a resistivity of 9µ O-cm where as Cu-
1.6 µ O-cm and Zn-6 µ O-cm 
23-Jan-15 3 AJITH VIJAYAN, EEE DEPT, GEC WAYANAD
? Cold work : Mechanical distortion of the crystal
structure decrease the conductivity of a metal
because the localized strains interfere with the
electron movement.
? Age hardening : It increases the resistivity of an
alloy.
Age hardening is a type of heat treatment used
in metallurgy to strengthen metal alloys. It is
also called precipitation hardening, as it
strengthens metal by creating solid impurities,
or precipitates, in the alloy that prevents
dislocations in the alloy's crystalline structure.
Its name comes from the point in the hardening
process in which the metal is aged, either by
heating it for an extended of time or keeping it
stored at a lower temperature for an extended
period before use.
23-Jan-15 4 AJITH VIJAYAN, EEE DEPT, GEC WAYANAD
Page 5


AJITH VIJAYAN
? Most important properties – thermal and 
electrical conductivity
? Silver has highest electrical conductivity, 
next is copper
? Conductivity of Cu is 5-10% less than silver.
? Supply of Cu is not abundant, hence Al which 
is light and has high conductivity is used 
commonly.
? Resistivity at 0°C & 20°C, µ ohm-cm
? Silver -1.51/1.629 
? Copper-1.589/1.724
? Al – 2.62/2.87
? Gold – 2.22/2.36
23-Jan-15
2 AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
AJITH VIJAYAN, EEE DEPT , GEC WAYANAD
? Temperature : Electrical resistance of most 
metals increases with increase in 
temperature and that of semiconductors and 
electrolytes decreases with increase of 
temperature.
? Alloying : Solid solution has a less regular 
structure than pure metal. The electrical 
conductivity of solid solution alloy decreases 
rapidly with increased alloy content. i.e
addition of small amount of impurities leads 
to increase in resistivity. Brass(63% Cu & 40% 
Zn) has a resistivity of 9µ O-cm where as Cu-
1.6 µ O-cm and Zn-6 µ O-cm 
23-Jan-15 3 AJITH VIJAYAN, EEE DEPT, GEC WAYANAD
? Cold work : Mechanical distortion of the crystal
structure decrease the conductivity of a metal
because the localized strains interfere with the
electron movement.
? Age hardening : It increases the resistivity of an
alloy.
Age hardening is a type of heat treatment used
in metallurgy to strengthen metal alloys. It is
also called precipitation hardening, as it
strengthens metal by creating solid impurities,
or precipitates, in the alloy that prevents
dislocations in the alloy's crystalline structure.
Its name comes from the point in the hardening
process in which the metal is aged, either by
heating it for an extended of time or keeping it
stored at a lower temperature for an extended
period before use.
23-Jan-15 4 AJITH VIJAYAN, EEE DEPT, GEC WAYANAD
? Applications : Age-hardened aluminum alloys
made with metals such as nickel, copper,
and zinc have frequently been used in the
construction of aircraft. The alloy Rene 41,
made from nickel alloyed with molybdenum ,
titanium, chromium, and cobalt , is used in
applications involving extreme strain and
temperature, such as jet engines.
23-Jan-15 5 AJITH VIJAYAN, EEE DEPT, GEC WAYANAD
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