Temperature sensors

Patent metadata

Field	Value
Publication number	US-2021190603-A1
Application number	US-201916723445-A
Country	US
Kind code	A1
Filing date	Dec 20, 2019
Priority date	Dec 20, 2019
Publication date	Jun 24, 2021
Grant date	—

Abstract

A temperature sensor including a sapphire optical fiber and a nanoporous cladding layer covering at least a portion of the sapphire optical fiber.

First claim

What is claimed is:

1 . A temperature sensor comprising:
a sapphire optical fiber; and a nanoporous cladding layer covering at least a portion of the sapphire optical fiber.

2 . The temperature sensor of claim 1 , wherein the nanoporous cladding layer comprises a refractory material.

3 . The temperature sensor of claim 2 , wherein the refractory material is a ceramic material.

4 . The temperature sensor of claim 3 , wherein the ceramic material comprises alumina.

5 . The temperature sensor of claim 3 , wherein the ceramic material is selected from the group consisting of: SiO 2 , TiO 2 , ZnO 2 , and ZrO 2 .

6 . The temperature sensor of claim 1 , wherein a refractive index of the sapphire fiber is less than a refractive index of the nanoporous cladding layer.

7 . The temperature sensor of claim 1 , wherein the nanoporous cladding layer comprises nanorods.

8 . The temperature sensor of claim 1 , wherein the nanoporous cladding layer comprises a thickness of at least 2 micrometers.

9 . The temperature sensor of claim 8 , wherein the nanoporous cladding layer comprises a thickness equal to or less than 8 micrometers.

10 . The temperature sensor of claim 1 , wherein the nanoporous cladding layer comprises a porosity of at least 25% of a total volume of the nanoporous cladding layer.

11 . The temperature sensor of claim 10 , wherein the nanoporous cladding layer comprises a porosity of at least 28% of the total volume of the nanoporous cladding layer.

12 . The temperature sensor of claim 11 , wherein the nanoporous cladding layer comprises a porosity of at least 30% of the total volume of the nanoporous cladding layer.

13 . The temperature sensor of claim 1 , wherein the sapphire optical fiber comprises a diameter of 400 micrometers to 500 micrometers.

14 . The temperature sensor of claim 13 , wherein the sapphire optical fiber comprises a diameter of 425 micrometers.

15 . The temperature sensor of claim 1 , further comprising a refractory housing covering at least a portion of the nanoporous cladding layer.

16 . The temperature sensor of claim 1 , wherein the sapphire optical fiber is configured to collect a plurality of readings of a temperature of molten steel over a period of time.

17 . The temperature sensor of claim 16 , wherein the temperature of the molten steel is 1540° C. to 1750° C.

18 . The temperature sensor of claim 16 , wherein the period of time is at least 10 minutes.

19 . A method of measuring temperature in an electric arc furnace, the method comprising:
providing a temperature sensor including an optical fiber and a refractory housing covering at least a portion of the optical fiber; introducing the temperature sensor into molten steel; and collecting a plurality of readings of the temperature of the molten steel with the temperature sensor.

20 . The method of claim 19 , wherein the optical fiber comprises a sapphire fiber.

21 . The method of claim 19 , wherein the temperature sensor comprises an air gap between the optical fiber and the refractory housing.

22 . The method of claim 21 , wherein the refractory housing comprises a first alumina layer and a second alumina layer.

23 . The method of claim 22 , wherein the first alumina layer is proximal the optical fiber relative to the second alumina layer, and wherein the second alumina layer is thicker than the first alumina layer.

24 . The method of claim 23 , wherein the thickness of the first layer is 2 millimeters, and wherein the thickness of the second layer is 4 millimeters.

25 . The method of claim 19 , wherein introducing the temperature sensor into molten steel comprises introducing the temperature sensor into the molten steel when the molten steel is at least 1540° C. for a duration of at least 10 minutes, and wherein collecting the plurality of readings of the temperature of the molten steel with the temperature sensor comprises obtaining thermal radiation spectra of the molten steel via the optical fiber at time intervals of one spectrum per second.

26 . A method for manufacturing a temperature sensor, comprising:
positioning an optical fiber at an angle of less than 45° from parallel to an evaporation source; rotating the optical fiber; while rotating the optical fiber, evaporating a deposition material at a deposition rate so as to generate an evaporation flux and coat at least a portion of the optical fiber with the deposition material.

27 . The method of claim 26 , wherein the angle is less than 30° from parallel to the evaporation source.

28 . The method of claim 27 , wherein the angle is less than 20° from parallel to the evaporation source.

29 . The method of claim 28 , wherein the angle is less than 10° from parallel to the evaporation source.

30 . The method of claim 29 , wherein the angle is less than 7° from parallel to the evaporation source.

31 . The method of claim 30 , wherein the angle is from 2° to 5° from parallel to the evaporation source.

32 . The method of claim 30 , wherein the angle is substantially parallel to the evaporation source.

33 . The method of claim 26 , wherein rotating the optical fiber comprises rotating the optical fiber at a rate of 10 to 60 revolutions per minute.

34 . The method of claim 26 , wherein the deposition rate is from 10 to 40 Å/second.

35 . The method of claim 26 , wherein evaporating the deposition material comprises irradiating the deposition material with an electron beam.

Assignees

• Ssab Entpr Llc
• Univ Iowa State Res Found Inc

Inventors

• Lu Meng
• Qian Jingjing
• Abraham Sunday O
• Petty Randy
• Werner Matthew J

Classifications

• H10F77/30

  Coatings (arrangements for preventing damage to photovoltaic cells caused by corpuscular radiation H10F77/80) · CPC title

• G02B6/02395

  Glass optical fibre with a protective coating, e.g. two layer polymer coating deposited directly on a silica cladding surface during fibre manufacture (G02B6/02052, G02B6/02057, G02B6/024, G02B6/032, G02B6/105, G02B6/14 take precedence; coating on fibre gratings G02B6/02104; multilayer core or cladding G02B6/036; reinforcing splice joints G02B6/2558; optical cables, i.e. comprising protective structures external to the protective coating such as a jacket or plural coated optical fibres G02B6/44; coating of glass to obtain optical fibres C03C25/104) · CPC title

• G01K11/12 Primary

  using changes in colour, translucency or reflectance · CPC title

• F27D21/0014

  Devices for monitoring temperature · CPC title

• C21C2005/5288

  Measuring or sampling devices · CPC title