The cube texture evolution of pure Ni during annealing Liu Wei Li xiaoling Tsinghua University

Research background Normal annealing Electric field annealing High magnetic field annealing

Research background Rolling assisted biaxially textured substrates

YBCO coated superconductor

Nickel substrate Pole figure of {111} cube texture

Nickel substrate Good space distribution Strong cube texture Small misorientation

Cube texture forming process Rolling reduction >95% Recrystallization Grain growth Annealing

Electric field annealing IF steel

Electric field annealing Al-Li alloy annealing in 450C for 3h (a) E＝2 kV (b) E=0KV

High magnetic field annealing IF steel H=10 T Retarded the recrystallization Intensified the {100}<110> texture Retarded the ND//<111> texture

High magnetic field annealing Zn–1.1%Al alloy H=32 T Scripta Materialia 46 (2002) 857–862

High magnetic field annealing Zn–1.1%Al alloy H=32 T without field; oriented parallel to the field; (c) tilted at +19° to the field about the TD (d) tilted at -19 ° to the field about the TD.

Motivation For superconductor substrate material cube texture and grain size are important The evolution of cube texture In normal annealing; In an electric field annealing; In a high magnetic field annealing.

Material Material： high pure Ni，purity is 99.999％ Reduction 98％ sample thickness is 90μm ND RD TD 90μm 1cm

Hardness curves for pure Ni annealed at 300ºC for different times Normal annealing Hardness curves for pure Ni annealed at 300ºC for different times

Cube texture evolution Cube texture evolution of pure Ni annealed at 300ºC for different times

Grain size Cube grain size and all grain size for pure Ni annealed at 300ºC for different times

Microstructure 300C-5min 300ºC-30min 300C-60min 300C-120min Dark to light shading indicates grains with orientations increasing deviations (up to 15) to {001}<100>. Fuchsia is cube grain, white is deviation more than 15º spread {100}<001> 300℃/20min 200℃/2h 300℃/5min 300℃/35min 300℃/60min 300℃/2h OIM maps of pure Ni annealed at 300ºC for different times

Electric field annealing Schematic illustration of the electric field annealing arrangement

Hardness Hardness curves for pure Ni annealed at 300ºC for different times in two different conditions

Microstructure of pure Ni annealed at 300ºC for different times 300ºC-0min 300ºC-30min 300ºC-120min (a) (b) (a) (b) Microstructure of pure Ni annealed at 300ºC for different times (a) E=0KV (b) E=2.0KV

Cube texture Cube texture fraction of pure Ni annealed at 300ºC for different times in the two different conditions

Grain size Grain size of pure Ni annealed at 300ºC for different times in the two different conditions

High magnetic field annealing sample ND Experiment parameter H=10T 300℃/2h The magnetic treatment sketch map

Angles choice

Cube texture (average) The red line is the cube texture fraction without a magnetic field Average cube texture fraction of different angles to magnetic direction annealed at 300℃ for 2h in H=10T magnetic field

Grain size The red line is cube grain size and the green line is all grain size without magnetic field The grain size of different angles to magnetic field annealed at 300℃ for 2h in H=10T magnetic field

Microstructure 300-2h-0(0º) 300-2h-2(24º) 300-2h-4(35º) OIM maps of different angles to magnetic field annealed at 300℃ for 2h in H=10T magnetic field 300-2h-9(90º) 300-2h-2(24º) 300-2h-4(35º) 300-2h-8(57.6º) 300-2h-6(53.3º)

Conclusion In normal annealing, with the annealing time increasing, the cube texture fraction and cube oriented grain size increase; Annealing in an electric field leads to smaller grain size for given annealing conditions compared with results without electric field annealing; Annealing in an high magnetic field is a complicated process which include the cube texture evolution and magnetic field effect.

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