COPPER VS ANNEALED COPPER
PROPERTIES OF COPPER
Copper is a reddish metal that is very soft and yielding. It has a great resistance to decay and maybe soldered easily. Its tensile strength varies between 3.15 and 4.73 tonnes per square centimetre. At 20oC, the specific gravity of copper is 8.94 gm/cc. It has a melting point of 1084oC and a boiling point of 2595oC. Hard drawn copper has a temperature coefficient of 0.00382 per oC, whereas annealed copper has a temperature coefficient of roughly 0.00393 peroC. The contact resistance is low. The plant's thermal conductivity is 385, and its atomic weight is 63.6. At 20oC, annealed copper has a resistivity of 1.72 x 10-8 ohm-m, while hard drawn copper has a resistivity of 1.77 x 10-8 ohm-m. Copper is soft when it is drawn and flexible after it is annealed.
PROPERTIES OF ANNEALED COPPER:
Copper is a reddish metal that is malleable and ductile. It has strong corrosion resistance and may be soldered easily. The tensile strength ranges from 3.15 to 4.73 tonnes / square centimetre. At 20°C, its specific gravity is 8.94 gm/cc. It has a melting point of 10840C and a boiling point of 25950C. The temperature coefficient of annealed copper is 0.00393 per oC, whereas the temperature coefficient of hard drawn copper is 0.00382 peroC. Its contact resistance is low. It has a thermal conductivity of 385 and an atomic weight of 63.6. At 20°C, annealed copper has a resistivity of 1.72 x 10-8 ohm-m while hard drawn copper has a resistance of 1.77 x 10-8 ohm-m. Hard drawn copper is springy and annealed copper is flexible.
ADVANTAGES AND DISADVANTAGES OF ANNEALED COPPER :
Copper's
resistivity and mechanical strength will both improve with hard drawing. Hard
drawn copper has a resistivity of 1.77 x 10-8 ohm-m, whereas
annealed copper has a resistance of 1.72 x 10-8 ohm-m. The copper
that has been drawn is springy, whereas copper that has been annealed is
flexible. Because localised stresses interfere with electron transport,
mechanical deformation of the essential structure reduces the metal's
conductivity. By increasing the regularity of the crystal lattice, subsequent
annealing restores electrical conductivity.
Surface hardening is necessary for some sectors of application, such as
switch contacts, to enable the material to give excellent wear resistance.
Particularly in the case of overhead power transmission, the resistivity of
hard pulled high conductivity copper is a function of tensile strength. Over a
temperature range of 0. to 150°C, the co-efficient of annealed copper wire is
0.000037/° C. At 20°C, the resistance per km of hard drawn copper for telephone
and telegraphic applications ranges from 3.615 to 3.657 ohms, with a breaking
load of 230 kg. The molecular structure of cold drawn copper is disturbed, and
the mechanical strength is reduced. The usage of the copper conductor in its
purest form is limited in electrical engineering applications, however alloying
has broadened its application.