CopperCopper is a metal with some very important properties, the main ones being its high electrical conductivity, its high thermal conductivity, its excellent resistance to corrosion, and its ease of fabrication, either hot or cold.

Copper is also ductile and malleable and has a relatively low melting point at just over 1 080°C.

The three basic commercial grades of copper that are available:

• Tough pitch copper, containing up to 0,1% oxygen

• Phosphorous deoxidized (PDO) copper, containing up to0,04% phosphorous

• Oxygen-free copper, containing no deoxidants.

The phosphorous deoxidised grade was originally developed to overcome problems encountered when flame welding tough pitch copper. It is now the standard commercial weldable grade used for pressure vessels and radiators. Oxygen-free grades have significantly higher electrical conductivity than oxygen-containing grades and are therefore used widely as electrical conductors.