Bulk Nanomaterials and Powders Consolidation Produced by Cyclic Extrusion Compression

The Cyclic Extrusion – Compression - reciprocating extrusion process (CEC) is one of severe plastic deformation methods (SPD), which allow to produce bulk nanomaterials without changing the initial shape of deformed samples. The results are presented showing that the average grains size and microbands thickness in aluminium alloys decrease below 100 nm. The investigations revealed that the average grains size is about 250 nm and 200 nm in polycrystalline and monocrystalline copper, respectively.The Cyclic Extrusion Compression method is also used to produce bulk materials by powder consolidation. The subgrains/nanograins inside the silver powder particles after the consolidation processes achieved the mean size of about 100 nm. Moreover, it has been found that inside structure observed by TEM, the consolidated powder granules consisted from nanometric twins of about 10 – 20 nm. This silver based powder consolidated by CEC method were extruded by hydrostatic extrusion method. The final product were the wires with a diameter of 3 mm, which were used to electrical contacts production.