Mechanical Property Evaluation of CuNb Composites Manufactured with High-Pressure Torsion

Copper is under consideration as the optimum material for both high heat flux applications and high-frequency pulsed magnets. One challenge is that copper has low strength which is problematic to deployment in these applications. One solution is to alloy copper with body center cubic (BCC) elements to improve its mechanical properties. However, the limited solubility of the BCC elements in copper requires high deformation processes to be used in order to manufacture these 3D composites. In this work high-energy ball milling combined with high-pressure torsion was used to manufacture 3D Cu-Nb composites. After the consolidation, the mechanical properties of the composites were measured using micro-and nano-hardness testing at room and elevated temperatures. The results indicated that after 10 turns during the high-pressure torsion consolidation, the mechanical properties of the composites were completely saturated, displaying uniform properties across the manufactured disk. Performing the high-pressure torsion at elevated temperature further improved the consolidation of the disk. The high-temperature nanoindentation also indicated a change in the deformation mechanism between 200 degrees C and 500 degrees C.

Automated summary

Copper is considered as a suitable material for high heat flux applications and high-frequency pulsed magnets, but its low strength poses a challenge. Alloying copper with body center cubic elements can enhance its mechanical properties. This study used high-energy ball milling combined with high-pressure torsion to manufacture 3D Cu-Nb composites. The mechanical properties of the composites were evaluated through hardness testing. The results showed that the mechanical properties of the composites reached saturation after a certain number of turns during the high-pressure torsion consolidation, exhibiting uniform properties across the manufactured disk. Performing high-pressure torsion at elevated temperature further improved consolidation. The high-temperature nanoindentation revealed a change in deformation mechanism within a certain temperature range.