Method of rolling NiW alloy tapes for coated conductors

Abstract

A method of rolling NiW alloy tapes for coated conductors belongs to the technical field of metal materials rolling. According to the method, a cylindrical NiW alloy ingot with a diameter not less than 10 mm is used to be rolled back and forth along the axial direction as a rolling direction, wherein the content of W is 57 at. %, and the axis of this ingot is perpendicular to the plane where the axes of working rollers are located. During rolling process, the cross sectional area reduction of the ingot is retained at 5% per pass. When the total cross sectional area reduction of the ingot is larger than 98% and the thickness of the tape is down to 60100 m, the rolling is stopped, and thus the NiW alloy tape is obtained. The method has the advantages that the negative influence generated when the NiW alloy tape is produced from a cuboid initial NiW alloy ingot can be reduced as much as possible, the yield of the NiW alloy tapes is increased, as well as relatively ideal effects can be obtained in terms of the surface biaxial texture, the length and the axial quality.

Claims

1. A method of rolling NiW alloy tape for coated conductors, comprising the following steps: rolling back and forth a cylindrical NiW alloy ingot with a diameter not less than 10 mm along an axis of the ingot, wherein the content of W is 57 at. % and the axis of the ingot is perpendicular to a plane where axes of working rollers are placed; and during the process of rolling the cylindrical NiW alloy ingot, cross sectional area reduction of the ingot is retained at 4-6% per pass; and the rolling is stopped when a total cross sectional area reduction of the ingot is larger than 98% and the thickness of the tape is down to 60100 m, and thus the NiW alloy tape is obtained.

2. The method of claim 1, wherein during the process of rolling the cylindrical NiW alloy ingot, the cross sectional area reduction of the ingot is retained at 5% per pass.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a relation curve of area reduction per pass and the thickness reduction per pass to the pass quantity of the cylindrical NiW alloy ingot.

(2) FIG. 2 is a schematic diagram of the total thickness reduction of the ingot and the rolling passes quantity in the processes of respectively rolling by using the cylindrical ingot at the area reduction per pass of 5% and the cuboid ingot at the thickness reduction per pass of 5% when having equal initial ingot thickness and final tape thickness;

(3) FIG. 3 is the total area reduction distribution of parts in the middle same as the initial cylindrical ingot in width, after redundant width spread parts near the two edges of the final NiW alloy tape produced by using the cylindrical NiW alloy ingot are removed;

(4) FIG. 4 is a pole figure (111) of the surface of the NiW alloy tape of which the content of W is 5 at. % and the thickness is 100 m;

(5) FIG. 5 is a pole figure (111) of the surface of the NiW alloy tape of which the content of W is 7 at. % and the thickness is 60 m;

SPECIFIC EMBODIMENTS

(6) Further detailed descriptions of this invention are described below in combination with embodiments and figures, but this invention is not limited to the following embodiments.

Embodiment 1

(7) Using the cylindrical NiW alloy ingot (the content of W is 5 at. %) in diameter of 10 mm as an initial ingot, the rolling is carried out back and forth in according to the thickness reduction per pass in Table 1 and rolling is stopped when the thickness is 100 m, and at that moment, the total area reduction is about 98.1%, and thus the NiW alloy tape is obtained after edge trimming treatment.

(8) An X-ray diffractometer is used to measure texture on the surface of the annealed NiW alloy tape to obtain the pole figure (111) of the surface of the tape as shown in FIG. 4. The pole figure shows that the surface of the NiW alloy tape has highly-concentrated cubic texture and can meet the requirement of the YBCO superconducting material on the flexible metal tape.

Embodiment 2

(9) Using the cylindrical NiW alloy ingot (the content of W is 7 at. %) in diameter of 12 mm as an initial ingot, rolling is carried out back and forth along in according to the pass thickness reduction in Table 1 and rolling is stopped when the thickness is 60 m, and at that moment, the total area reduction is about 99.0%, and thus the NiW alloy tape is obtained after edge trimming treatment.

(10) An X-ray diffractometer is used to measure texture on the surface of the annealed NiW alloy tape to obtain the pole figure (111) of the surface of the tape as shown in FIG. 5. The pole figure shows that the surface of the NiW alloy tape has highly-concentrated cubic texture and can meet the requirement of the YBCO superconducting material on the flexible metal tape.

(11) Table 1 shows the approximate thickness reduction per pass which is obtained by calculation when the area reduction per pass of the cylindrical NiW alloy ingot is retained at 5%.

(12) TABLE-US-00001 TABLE 1 Reduction Area Thickness Area Reduction per Reduction Reduction per Pass per pass (%) pass (%) Pass per pass (%) pass (%) 1 5.0 12.2 21 5.0 5.13 2 5.0 7.9 22 5.0 5.12 3 5.0 7.0 23 5.0 5.11 4 5.0 6.5 24 5.0 5.10 5 5.0 6.2 25 5.0 5.09 6 5.0 6.0 26 5.0 5.08 7 5.0 5.8 27 5.0 5.07 8 5.0 5.7 28 5.0 5.06 9 5.0 5.6 29 5.0 5.055 10 5.0 5.5 30 5.0 5.050 11 5.0 5.45 31 5.0 5.045 12 5.0 5.40 32 5.0 5.040 13 5.0 5.35 33 5.0 5.037 14 5.0 5.30 34 5.0 5.033 15 5.0 5.27 35 5.0 5.030 16 5.0 5.24 36 5.0 5.027 17 5.0 5.21 37 5.0 5.024 18 5.0 5.19 38 5.0 5.022 19 5.0 5.17 39 5.0 5.019 20 5.0 5.15 40 5.0 5.017