Hard drawn copper is difficult to work with and stranding and bunching of the finer wires in this state would be very difficult. By heat treating the copper at the correct temperatures the ductility can be restored to make the cable soft and flexible again. The heat treating process is known as annealing and the resulting metal is known as soft annealed copper. The degree of annealing is controlled by temperature and time, copper wire is used with different degrees of annealing depending on the application.Hard drawn copper has significantly higher tensile strength than soft annealed copper and is used as overhead wire whereas the soft annealed copper is flexible and has somewhat improved conductivity over hard drawn copper conductor.
