A European consortium is evaluating materials for the construction of a new supersonic transport aircraft that may replace Concorde. Current designs propose to use an aluminium alloy for the fuselage which is required to have superior creep resistance and damage tolerance to the Concorde alloy 2618A. Promising results have been obtained with extruded Al-Cu alloys containing minor additions of magnesium and silver which stimulate hardening by the relatively stable V precipitate. Data is presented which shows that these alloys have tensile and accelerated creep properties which are better than those of competing commercial alloys of the 2000 series, together with satisfactory levels of fracture toughness. Of the four experimental alloys studied, the optimal composition is Al-5·6Cu-0·45Mg-0·45Ag-0·30Mn-0·18Zr (wt-%).

Vapor Deposition (IBAD-MOCVD) REBCO conductors on Hastelloy substrates is reported for axial tensile strains up to 0.5% and up to 100,000 cycles. Failure mechanisms are investigated via microstructural studies. Results show that REBCO conductors retain electrical performance for 10,000 cycles at ε=0.35% and ε=0.45% strain, and ε=0.5% for 100 cycles. The main cause of fatigue degradation in REBCO conductors is crack propagation that initiates at the slitting defects that result from the manufacturing process.

(RE)Ba2Cu3O7−x (REBCO) conductors have the potential to enable a wide range of superconducting applications over a range of temperatures and magnetic fields (Vincent et al 2013 IEEE Trans. Appl. Supercond. 23 5700805), yet AC applications and devices with a charge/discharge cycle may be limited by the conductor fatigue properties. Here the fatigue behavior of GdBa2Cu3O7−x (GdBCO) conductors grown by reactive co-evaporation on stainless-steel substrates is reported for axial tensile strains, ε, up to 0.5% and 100 000 cycles. Failure mechanisms are investigated via microstructural studies and compared with a commercially available IBAD/MOCVD REBCO conductor. Results show that GdBCO/stainless-steel conductors retain their transport critical current for 10 000 cycles at ε = 0.35% and ε = 0.45%, and for 1000 cycles at ε = 0.50%. The main cause of fatigue degradation in GdBCO conductors is crack propagation and delamination that initiates at the edge of the conductor due to manufacturing defects.

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