Mechanical behaviour of copper 15% volume niobium microcomposite wires

Abstract

Cu-Nb microcomposites are attractive in magnet pulsed field technology applications due to their anomalous mechanism of mechanical strength and high electrical conductivity. In this sense, recently it was conceived the use of Cu 15% vol. Nb wires to operate as a high tensile strength cable for a diamond cutting tool (diamond wires) for marble and granite slabbing. The multifilamentary Cu 15% vol. Nb composite was obtained using a new processing route, starting with niobium bars bundled into copper tubes, without arc melting. Cold working techniques, such as swaging and wire drawing, combined with heat treatments such as sintering and annealing, and tube restacking were employed. The tensile property of the composite was measured as a function of the niobium filaments dimensions and morphology into the copper matrix, in the several processing steps. An ultimate tensile strength (UTS) of 960 MPa was obtained for an areal reduction (R = Ao/A, with Ao-initial cross section area, and A-final cross section area) of 4x10(8) X, in which the niobium filaments reached thickness less than 20 nm. The anomalous mechanical strength increase is attributed to the fact that the niobium filaments acts as a barrier to copper dislocations

Mechanical and superconducting properties of Nb3Sn wires with Nb-rod-processed CuNb reinforcement

“…A Cu-20 vol%Nb alloy was prepared using a new Nb rod process [15][16][17] with the cold-worked CuNb composites between the Cu jacket and the Nb barrier was drawn to a final size with an outer diameter of 0.8 mm. The wire was heat-treated at 670 • C for 96 h. Table 1 shows the specifications and a cross sectional view of the Nb-rod-processed and in-situ-processed CuNb/Nb 3 Sn wires.…”

Measurement of Electrical Conductivity and Resistivity of Cu-Nb18% Microcomposite Conductor and Its Welded Joint

“…Tyrimuose naudojamas 4,2×2,4 mm skersmens Cu-Nb 18 % mikrokompozitinis laidininkas (4 pav. ), kuriame Nb gijų skersmuo <15 nm (Filgueira et al, 2001). Tokio Cu-Nb 18 % laidininko tempimo stipris R m siekia 1100-1500 MPa, takumo riba R e -850 MPa, santykinis pailgėjimas S -4,2 % (Mikalauskas et al, 2020), elektrinis laidumas σ ~ 65 % IACS (Bartkevičius & Novickij, 2009).…”