Development of structure and properties in bimetallic Al/Cu sandwich composite during cumulative severe plastic deformation

Abstract

Development of modern materials is non-negligibly connected with enhancement of their mechanical and utility properties, which can advantageously be performed via optimized deformation processing. The study presents preparation of Al/Cu sandwich composite, reinforced with Cuwires, by the twist channel angular pressing (TCAP) method. Extrusion of the sandwich composite via single and double pass TCAP was simulated using the finite element method, and performed experimentally. The predicted deformation behaviour was verified by 3 D Micro-CT scanning, as well as detailed microstructure observations. The results showed that already the single TCAP resulted in substantial deformation strengthening of both the component metals, and the effective strain imposed within the Alsheath reached the value of 5 after the second pass. The Alsheath also featured homogeneous distribution of the lowest absolute values of residual stress, and the smallest average grain size of 1.66 µm. The Cu grains within both the composites were also significantly refined, to almost 3 µm after the second pass. Nevertheless, the observed parameters featured slight variations across the composites’ cross-sections, which can be attributed to the plastic flow behaviour phenomena. The severe imposed shear strain also resulted in increase in microhardness and imparted changes in the thermal conductivity.

High Pressure Torsion of Copper; Effect of Processing Temperature on Structural Features, Microhardness and Electric Conductivity

“…Among the possibilities how to increase the mechanical properties and simultaneously maintain advantageous electric conductivity is to use modern methods and fabricate Cu-based composites featuring strengthening elements (e.g., powder-based composites with additions of Cr [ 5 ], Al 2 O 3 [ 6 ], and carbon nanotubes [ 7 ], or clad composites consisting of Cu plus Al [ 8 , 9 , 10 , 11 ], Al and Mg [ 12 ], Nb [ 13 ], and FeSiBCuNb [ 14 ]). A favorable way how to increase the mechanical properties without deteriorating the electric ones can also be optimized deformation (thermomechanical) treatment–such as fabrication of electro-conductive wires via rotary swaging [ 15 ] or processing via methods of severe plastic deformation (SPD) [ 16 ].…”

Influence of (Sub) Structure Development within Rotary Swaged Al–Cu Clad Conductors on Skin Effect during Transfer of Alternating Current

“…Previously published works dealing with Al plus Cu composites mostly focused on their design [27,28], fabrication methods [14,29], deformation behaviour [30], structure characterization [31][32][33], and determination of mechanical properties [34,35]. Several studies also dealt with basic characterization of their electric properties [13].…”

Fabrication of Magnesium-Aluminum Composites under High-Pressure Torsion: Atomistic Simulation

“…One of the possible ways to obtain metallic composites is high-pressure torsion (HPT), during which high compressive and shear stresses result in the formation of the composite structures. To date, several types of composite materials were obtained by HPT from metallic plates: Al-Cu [7][8][9][10][11][12][13], Al-Mg [14][15][16], Al-Nb [17], and Al-Ti [18]. Since severe plastic deformation can increase the diffusion in the materials [19,20], in situ composites can be obtained by HPT through the bonding of different metals, which can lead to the formation of new intermetallic phases.…”