OFHC Oxygen-Free Copper Wire Rod

The OFHC copper wire rod  produced by Copper Italia is a single-phase material as it does not contain oxides and therefore it is greatly more ductile and workable than normal ETP wire rod.

Thanks to the high capacity of the melting furnace and the hold time of the molten copper (characteristics universally recognised in the industry as prerequisites for the production of premium quality wire rod), the level of oxygen in our wire rod is maximum 1-2 ppm. A small amount of oxygen results in few imperfections in the internal structure of the wire rod.  Higher levels of oxygen, i.e. greater than 4 ppm, may cause problems in downstream manufacturing processes.

Our fully automated control at all stages of the process ensures a marked step forward in terms of both quality and reliability compared to all previous production technologies of copper wire rod.

DATA SHEET – CHARACTERISTICS  OF THE OFHC COPPER ANODE.

OFHC Copper is the only one produced following a completely oxygen-free process. It meets ASTM B 170 standards and was initially developed to meet the particular needs of modern industrialisation.

The production of OFHC copper  (see table) ) starts with the selection of copper cathodes of a high level of quality and purity, which are melted in an induction oxygen-free atmosphere where any oxygen residual traces on the cathodes are eliminated.

The molten copper obtained is then poured in a holding furnace via a duct in a completely oxygen-free atmosphere, thanks to the gaseous components that prevent contamination. This process also prevents the inclusion of any potentially harmful components in the holding furnace from where the wire rod is then extracted.

COARSE GRAIN STRUCTURE HELPS PREVENT ROUGHNESS AND ENSURE EVEN COATING.

In copper, like in other metals, oxidation and other impurities can be revealed by analysing the grain structure. The impurities are subject to etching by plating solutions. Small particles of undissolved impurities can cause roughness, whereas the purity and structure of OFHC copper ensures a compact structure with an impurity-free smooth surface.

THE ABSENCE OF ADDITIVES MAKES  GALVANIC BATHS MORE EFFICIENT.

Since no de-oxidising agents or additives are used in the production of OFHC copper, there are noresidual contaminants. In electroplating terms, this means a virtually total elimination of insoluble particles in the bath.

LESS RESIDUE MEANS LESS NEED FOR CLEANING THE PLATING VATS.

The use of OFHC copper results in less residue in the plating vats. The absence of oxides (not detectable by ASTM microscopic tests), combined with the extremely low level of impurities, contribute to minimize the amount of residue present in the bath.

 CHEMICAL AND PHYSICAL PROPERTIES OF OFHC COPPER: 

Electrical conductivity

a 20oC / 68 F – soft annealed

00.0-101.5 % IACS

58.0-58.9 m/ohm mm2

a 20oC / 68 F – fully cold worked

97.0-97.7 % IACS

56.3-56.6 m/ohm mm2

Thermal conductivity

a 20oC / 68 F

395 W/Km

0.094 cal, cm/cm2soC

Coefficient of  thermal expansion

da 25 a 100oC / da 77 a 212 F

0.0000168 per oC

0.00000933 per F

da 20 a 300oC / da 68 a 572 F

0.0000177 per oC

0.00000983 per F

Resistance to external agents

Resistance to hydrogen embrittlement

good

Corrosion Resistance

good

 

 

Cu-OF versus Cu-ETP

ELECTROLYTIC COPPER
(ETP)

  OXYGEN-FREE COPPER
(OFHC)

Silver

.0013

.0012

Sulphur

.0015

.0012

Arsenic

.0006

.0002

Lead

.0010

.0005

Antimony

.0010

.0005

Bismuth

.0001

.00003

Selenium

.0003

.0001

Tellurium

.0001

.00005

Pond

.0004

.0001

Nickel

.0014

.0005

Zinc

.0004

.00005

Oxygen

.0340

.0003

Conductivity (IACS)

100.7%

101.5%

 

 

Comparison of Electrical Characteristics

Copper UNI
5649/1

Max Resistivity (Mass) (Omega*g)/m2

Max Resistivity (Volume)(Omega*mm2)/m

Min Conductivity

m/(Omega*mm)

Min Conductivity

IACS % min

CU-ETP

0,155 96

0,0175 44

57

98,28

CU-OF

0,153 28

0,017 241

58

100

DATA SHEET – CHEMICAL AND PHYSICAL PROPERTIES OF OFHC WIRE ROD.

The chemical and physical properties of our OFHC wire rod are shown in the table below.

CHEMICAL AND PHYSICAL PROPERTIES OF OFHC COPPER:

Electrical conductivity

a 20oC / 68 F – soft annealed

00.0-101.5 % IACS

58.0-58.9 m/ohm mm2

a 20oC / 68 F – fully cold worked

97.0-97.7 % IACS

56.3-56.6 m/ohm mm2

Thermal conductivity

a 20oC / 68 F

395 W/Km

0.094 cal, cm/cm2soC

Coefficient of thermal expansion

da 25 a 100oC / da 77 a 212 F

0.0000168 per oC

0.00000933 per F

da 20 a 300oC / da 68 a 572 F

0.0000177 per oC

0.00000983 per F

Resistance to external agents

Resistance to hydrogen embrittlement

good

Corrosion resistance

good

DATA SHEET – QUALITY STANDARDS

Our products meet the following international standards.

QUALITY STANDARDS

Outokumpu
designation

National designation

Germany
DIN

UK
BS

France
NF

USA
UNS

Sweden
SS/SIS

Denmark
DS

Norway
NS

Finland
SFS

Oxygen
free

OF-OK™

1787
OF-Cu

6071
1981
Cu-OF

Cu-Cl

C10200OF
ASTM B170-82
grade 2

6011

6011
Cu-OF

16011
Cu-OF

2905
Cu-Of

DATA SHEET: PACKAGING USED FOR OFHC WIRE ROD.

vergelle-ofhc-2

OFHC copper wire rod comes in the following packaging, depending on the wire rod diameter:

18mm coils
vergelle-ofhc-rot8

16mm coils
vergelle-ofhc-rot16

20mm coils
vergelle-ofhc-rot20