Copper

Copper belongs to heavy metals. Its specific weight is about 8.93 kg / cm³, and the melting temperature is 1083 ° C. The copper does not have any properties of allotropic modifications. The mechanical properties of the copper are highly dependent on the state or possible previous mechanical or thermal processing. Copper is a very plastic material that can be processed by deformation, both in cold and hot conditions. For welding, copper is not the most suitable, as it creates difficulties in the required rapid heat removal. During gas welding, due to the high propensity of gas absorption, increased porosity and brittleness may occur.

The mechanical properties of the copper are highly dependent on the state or possible previous mechanical or thermal processing. Copper is a very plastic material that can be processed by deformation, both in cold and hot conditions. For welding, copper is not the most suitable because it creates difficulties in the required rapid heat removal. During gas welding, due to the high propensity of gas absorption, increased porosity and brittleness may occur.

Basic properties of copper

reddish colors,
relatively high volume mass ρ = 8.9 g / cm3
melts at 10830 C
An excellent conductor of electric current, the best among non-precious metals, but its primers considerably reduce conductivity.ž
good heat conductor.
Corrosive is air-resistant because it is created on the surface of green patina (CuO3xCu (OH) 2) which is dense and protects it from further corrosion.
Copper is a material of low tensile strength and is very elastic.
The copper has a cubic surface-centering grid and a structure of polyhedron crystals

Wide application in electrical conductors for making conductors. Pure copper does not have much use in aerial constructions, but its alloys are used. It is well-alloyed with zinc, aluminum, lead, tin, and beryllium. Copper alloys have a much better tensile strength than pure copper, but they are so weak that they are more heat insulators.

Chemical properties

oxidized on pure, humid or salty air. With CO 2 there is a patina, which spreads to decay,
it is scorched by sea and ordinary water, but not distilled,
it is destroyed by ammonia and sulfur, so rubber insulation can not be placed directly on it,
it dissolves in nitric and sulfuric acid

Copper alloys

Copper alloys can be classified according to the way of making, the purpose, the number of the main alloying elements, the nature of the main alloying elements

a) Zinc alloys - mesins:

two-component Cu-Zn alloys (conventional brass)
special Cu-Zn alloy special alloys
three-component Cu-Ni-Zn alloys (new silver :)
three-component alloy Cu-Zn-Sn (red cast). These are alloys representing a transition from brass to bronze.

b) Copper alloys without zinc - bronze, are two, three and complex Cu-alloys:

Calyx bronze - Cu-Sn alloys
Aluminum bronze - Cu-Al alloys
Nickel bronze - Cu-Ni alloys
Lead and lead-acid bronze - Cu-Pb and Cu-Sn-Pb alloys
Bronze silicon - Cu-Si alloys
Beryllium bronze
Manganese bronze

c) Copper alloys for soldering and welding:

Mesingani lem
Silver Lime

The most famous copper alloys are those with zinc-alloying and alloys in which zinc is not the main alloying element (bronze).

Standard Copper Types:

DIN	EN	ASTM	NF	UNI	BS	GOST
SE-Cu 2.070		~C 10 300	~Cu-c1	~Cu-OF	C 103
SW-Cu 2.076	Cu-DLP	~C 12 000	~Cu-b2	~Cu-DLP	C 106	~M1R
SF-Cu 2.090	Cu-DHP	~C 12 000	~Cu-b1	~Cu-DHP	C 106

The cold treatment of hardness and the tensile strength of the copper increase considerably. Tensile strength depends on the chemical composition, thermal and mechanical processing: