Al/C60 Nanocomposites Fabricated by High-Pressure Torsion

Abstract

Al-2 vol pct fullerene (C60) composites with relative densities of >0.98 are manufactured by high-pressure torsion of ball-milled powders under an applied pressure of 6 GPa. A considerable Al grain refinement to~53 nm and a homogeneous distribution of fullerenes give rise to a very high hardness of 152 Hv and yield stress of 405 MPa. Nevertheless, the poor tensile ductility due to the low work-hardening rate is achieved.

Thermal Stability, Grain Growth Kinetics, and Mechanical Properties of Bulk Ultrafine-Grained AA6063/SiC Composites with Varying Reinforcement Sizes

“…[2,3] Severe plastic deformation (SPD) methods are being extensively used to develop bulk UFG composites. Accumulative roll bonding (ARB), [4,5] equal channel angular pressing (ECAP), [6] high-pressure torsion (HPT), [7] and friction stir processing (FSP) [8,9] are well-established SPD techniques used to develop bulk UFG composites. These deformation techniques store a high fraction of dislocation density in the matrix, refine the microstructure in the UFG/NS regime and hence impart extraordinary properties to UFG composites.…”

“…[16] The dislocation structures are even highly thermally unstable compared to the grain structures developed by various SPD techniques. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] Therefore, the thermal stability of UFG composite materials developed by any SPD process should be thoroughly examined before considering them for any engineering application.…”