The feasibility of hydrostatic extrusion (HE) of ultrafine grained (UFG) AA1070 has been investigated. The UFG material was produced by equal channel angular pressing (ECAP) using a scaled-up, two-turn, S-shape channel. Four passes of ECAP were followed by three passes of HE, which reduced the billet cross-section from a 26 x 26 mm2 square to 5 mm diameter round section. The average grain size of 0.6 micron after ECAP was reduced to 0.4 micron by HE. The strength and hardness increased by ECAP were further increased by HE. Ductility was reduced by ECAP, however, it remained constant during HE. The suggested sequence of operations seems to be a feasible option for producing UFG billets for shaping elongated products.
- UFG aluminium
- hydrostatic extrusion
- ultrafine grained aluminium
- equal channel angular pressing