▎ 摘　　要

True bulk nanostructured composites promising for a wide range of applications however being difficult to produce using established engineering techniques. Most of previous works aimed to design of Cu graphene composite used the approach of high temperature sintering inevitably associated with growth of Cu grains. Another advantageous approach of composites consolidation allowing to avoid heating of the sample is shear deformation under high pressure that has been earlier used for Al-graphene composite. Our work reports the first attempt of Al-graphene composite consolidation by means of is high pressure torsion (HPT). Two-step processing by constrained and non-constrained HPT was applied to produce bulk Cu-graphene composite with nanoscaled Cu grains laminated by graphene. After the constrained HPT high and low graphene content layers were interspersed in the microstructure. The second step of not-constrained HPT led to the refinement of graphene agglomerates to the range of 10 nm and Cu grains to the range of 100 nm with quite uniform distribution of graphene, preserving the equiaxial shape of the grains seldom in case of the composite structure. The process significantly increased microhardness of Cu-graphene composite from 1450 to 1900 MPa in the edge region after consolidation with even more pronounced increase from 1900 to 2950 after following constrained HPT. However, infusion of graphene resulted in a prominent decrease of both ductility from 15 to 4% and strength of the material. Brittle failure with low value of critical fracture stress should be related to the role of graphene as an obstacle for the dislocation movement. The dynamic recrystallization in the Cu-graphene composite during severe plastic deformation by not-constrained HPT suggests also that dispersed graphene may play role in the dislocation sinking at the micro-grains boundaries. The obtained results contribute to figuring out the major issues of Cu and graphene interaction under pressure and can be helpful in validation of prospective research plan in this field.