Copper/pearlitic steel macrocomposites

It is well known that drawing of patented pearlitic steel wires can realize tensile strength of more than 4 GPa for final diameters < 0.1 mm. This value is far too optimistic for the pearlitc steel tube component in macrocomposites since the achievable strength decreases with the increase of the patented cross-section. The 'rod-in-tube' experiments are performed with air patented tubes of a 0.6 wt.% carbon steel. The figure shows the ultimate tensile strength and the electrical conductivity of two Cu/pearlitic steel composites as a function of drawing strain. The composite with 56 vol.% copper yields an ultimate tensile strength of 1.53 GPa after a logarithmic drawing strain of eta = 4. This gives a strength level of about 3 GPa for the steel mere jacket. The conductivity of the composites corresponds roughly to the volume fractions of copper.