Effect of continuous extrusion on the microstructure and mechanical properties of a CuCrZr alloy

A Cu–0.16Cr–0.12Zr alloy with an initial grain size of about 400 μm was extruded by continuous extrusion forming (CEF), where severe plastic deformation and precipitation process occurred. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to examine the microstructure and morphology of the precipitates. Experimental results show that a notable grain size reduction to sub-micron scale is obtained through continuous dynamic recrystallization and precipitates maintain a fine and disperse morphology after the CEF process. These two features are considered as the effective ways to improve the strength and ductility of the CuCrZr alloy after cold deformation and subsequent aging process without a significant decrease of electrical conductivity.