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The Cu-Cr composite material is widely used as an electrode material in a vacuum circuit breakers used in electric power systems. It is generally produced by sintering processes, and then Cr particles were refined in the surface part. Using the Compressive Torsion Process (CTP) which is one of the severe plastic deformation processes, the Cu-Cr composite powder can be fully dense consolidated without sinter, and the Cr particles are refined in surface layer portion at the same time. In this study, the CTP was applied to the laminated material of Cu-Cr composite and Cu powders and the possibility of consolidation and Cr particle refinement of the laminated material was investigated. The consolidation of Cr-Cu/Cu laminated powder was possible by the CTP, and Cr particles near a drive end were extremely refined. Hardness and tensile strength of the laminated material were medium between both single Cu-Cr and Cu specimens. It means they were largest and the same level as Cu-Cr single composite near the end of a cylindrical specimen, and decreased gradually toward the middle part of Cu layer until the same level as Cu single material.

The aluminum foam sandwich (AFS) was examined its formability in die forging. The AFS specimens with different lengths were prepared by roll and bonding precursor process and the AFS specimens were compressed with single or double projected dies. The foam core in the AFS is successfully compressed only in a part under a die projection even at room temperature. However some parts of AFS specimens near the foot of a projection and between the double projections were deformed without touching with the die faces. In the case of single projection die, the length of AFS specimens affected greatly the compressive strain near the foot edges of projections. However, in the case of double projection die, the strain of AFS between the projections was not affected by the specimens’ length.