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The new machine for deformation of metals and alloys by Cyclic Extrusion Compression method has been presented. The special, 600 kN capacity press was designed and build to deform materials by the CEC way. The press is equipped by microprocessor control system for hydraulic steering and measurement of the forces exerted by tools. The microstructure of AlMgSi (6082) samples deformed by new CEC press showed the nanometric features such as dimension of grains below 100 nm and large disorientation between nanograins. The nanostructure was found after the 24 cycles of the CEC ( = 16). The simulation of plastic flow in CEC process was performed by a DEFORM software. The process has been modelled in relation to the technically pure aluminium and 6082 aluminium alloys deformed with the reduction of sample diameter from 10 to 8.5 mm and next increase from 8.5 to 10 mm in a single CEC cycle. It was found that at suitably selected values of counterforce the tensile circumferential stresses occurred behind the matrix where radial extrusion took place. Increasing the level of hydrostatic pressure it was possible to prevent an increase of the dangerous tensile stresses. Based on the data from numerical simulation of the CEC processes a special diagram has been prepared, which facilitates suitable choice of the counterforce level.

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Batch SPD processes have a limited scope for being used on an industrial scale. More feasible are continuous processes among which the new SPD process of Incremental ECAP (IECAP) is an attractive option. In this paper, a double-billet version of I-ECAP, which doubles process productivity, is presented. The concept of the process is first checked using the finite element (FE) method. FE simulation results are the basis for the design of an experimental rig. Trials of nanostructuring of 10x10x200 Al 1070 billets are carried out with the forces on the reciprocating die and the feeder measured. Metallurgical samples after 4 and 8 passes of I-ECAP (route BC) are investigated using TEM. Tensile properties after 8 passes are established. All these results show that the new SPD process of I-ECAP gives the results comparable to those obtained by a classical batch ECAP with the added capability of dealing with much longer (possibly infinite) billets.

Because of the well known virtues of low cost and high productivity, metal forming technology is well suited for mass production of metal micro-components. However, scaling down metal forming processes proves to be problematic because, among other factors, the relatively coarse grain (CG) structure of micro-billets leads to non-uniform material flow and lack of repeatability during microforming. A substantial grain size reduction below one micron should help to prevent these problems. The aim of the presented study is to investigate a possibility of using an ultrafine grained (UFG) metal for micro-extrusion. The material used for this purpose is CP Cu often used for electrical applications. The UFG version of Cu is produced by severe plastic deformation at room temperature using up to 8 passes of equal channel angular pressing. The microstructure and compression properties of the UFG version of the material are tested. The microforming process of backward extrusion is carried out at room temperature using half cylindrical billets. The extrusion force, grain flow, shape representation and surface quality of the extruded micro-components are compared

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The influence of very large deformations on the properties and microstructures of A199.95 and A199.992 is investigated. The very large deformations are imposed by the cyclic extrusion-compression (CEC) method, which combines extrusion and compression processes. It is found that above true strains of 4 and 8 respectively, the compression proof stresses of A199.992 and A199.95 stabilize. The property stabilization appears to result from the increasing incidence of micro bands which leads to the final constancy of the microstructure parameters. The homogeneous chess-board like microstructure forms during the deformation by the CEC method, as the result of rearrangement of microstructure by the mutually crossing microbands leading to the final dominance of persistent macro shear bands.