Tungsten wire and tungsten product

Patent metadata

Field	Value
Publication number	US-11761065-B2
Application number	US-202017604859-A
Country	US
Kind code	B2
Filing date	Apr 13, 2020
Priority date	Apr 26, 2019
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A tungsten wire is a tungsten wire containing tungsten or a tungsten alloy, a diameter of the tungsten wire is at most 100 μm, and a total number of torsional rotations to breakage per length of 50 mm of the tungsten wire is greater than or equal to 250×exp(−0.026×D) when a tension that is 50% of a breakage tension of the tungsten wire is applied as a load, D denoting the diameter of the tungsten wire.

First claim

The invention claimed is:

1. A tungsten wire containing tungsten or a tungsten alloy, wherein
a diameter of the tungsten wire is at most 100 μm, and
in a state that a tension that is 50% of a breakage tension of the tungsten wire is applied to the tungsten wire as a load, a total number of torsional rotations to breakage per length of 50 mm of the tungsten wire is greater than or equal to 250×exp(−0.026×D), where D denotes the diameter of the tungsten wire.

2. The tungsten wire according to claim 1 , wherein
a tensile strength of the tungsten wire is at least 4800 MPa.

3. The tungsten wire according to claim 1 , wherein
a tungsten content of the tungsten wire is at least 90 wt %.

4. A tungsten product comprising: the tungsten wire according to claim 1 .

5. The tungsten product according to claim 4 , wherein
the tungsten product is a saw wire, a twisted wire, a rope, or a medical device component.

6. A tungsten wire containing tungsten or a tungsten alloy, wherein
a diameter of the tungsten wire is at most 100 μm, and
in a state that a tension that is 50% of a breakage tension of the tungsten wire is applied to the tungsten wire as a load, a total number of torsional rotations to breakage per length of 50 mm of the tungsten wire is greater than or equal to 250×exp(−0.026×D), where D denotes the diameter of the tungsten wire,
wherein the tungsten wire is formed by a wire drawing process,
wherein, in the wire drawing process, the tungsten wire is subjected to an elevated-heat drawing,
wherein the elevated-heat heat drawing is two drawings before a final drawing in the wire drawing process and is performed at a temperature equal to a temperature of a preceding heat drawing that precedes the elevated-heat drawing in the wire drawing process, and
wherein the preceding heat drawing and the elevated-heat drawing are performed successively.

7. The tungsten wire according to claim 6 , wherein
a tensile strength of the tungsten wire is at least 4800 MPa.

8. The tungsten wire according to claim 6 , wherein
a tungsten content of the tungsten wire is at least 90 wt %.

9. A tungsten product comprising: the tungsten wire according to claim 6 .

10. The tungsten product according to claim 9 , wherein
the tungsten product is a saw wire, a twisted wire, a rope, or a medical device component.

11. The tungsten wire according to claim 6 , wherein
the temperature at which the elevated-heat drawing is performed is greater than a temperature at which the final drawing is performed, and
wherein the temperature at which the final drawing is performed is room temperature.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Kanazawa Tomohiro
• Kohyama Naoki
• Iguchi Yoshihiro
• Nakai Yui

Classifications

• C22F1/18 Primary

  High-melting or refractory metals or alloys based thereon · CPC title

• C22C27/04 Primary

  Alloys based on tungsten or molybdenum · CPC title

• C22F1/00

  Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working (apparatus for mechanical working of metal B21, B23, B24) · CPC title

• A61L29/02

  Inorganic materials · CPC title

• A61L31/022

  Metals or alloys · CPC title