Investigation on the CuNb "in-situ" microcomposites conductivity during the process of tensile testing

Resistivity of the high strength CuNb microcomposites have been investigated just in the process of tensile testing at the temperatures of 293 K and 77 K. Two processes determine the character resistivity-strain dependencies in microcomposites during elongation: the increase of the lattice defects concentration in copper which leads to the increase of resistivity; the decrease of compression of Cu lattice along the conductor axis which leads to decrease of resistivity. It was shown that the deformation of microcomposite wires at 77 K with following relaxation at 293 K led to the increase of ultimate tensile strength at room temperature. This increase could be as large as 3-6% depending on the level of strain applied at cryogenic temperature.