46 results about "Sapphire fiber" patented technology

In accordance with one exemplary embodiment the invention provides a multi-parameter fiber optic sensing system with an aperiodic sapphire fiber grating as sensing element for simultaneous temperature, strain, NOx, CO, O2 and H2 gas detection. The exemplary sensing system includes an aperiodic fiber grating with an alternative refractive index modulation for such multi-function sensing and determination. Fabrication of such quasiperiodic grating structures can be made with point-by-point UV laser inscribing, diamond saw micromachining, and phase mask-based coating and chemical etching methods. In the exemplary embodiment, simultaneous detections on multi-parameter can be distributed, but not limited, in gas / steam turbine exhaust, in combustion and compressor, and in coal fired boilers etc. Advantageously, the mapping of multiple parameters such as temperature, strain, and gas using sapphire aperiodic gratings improves control and optimization of such systems directed to improve efficiency and output and reduce emissions.

A retro-reflective sensor for sensing mechanical, chemical or temperature related information, is disclosed. The sensor is formed of an optical waveguide suitable for use in-situ in a high temperature environment having a Bragg grating written into a core region thereof with short-pulsed electromagnetic radiation, said optical waveguide having a glass transition temperature substantially higher than that of silica. Preferably the sensor is written into a length of sapphire fiber or within a zirconium waveguide. Preferably the pulse duration of the short pulsed electromagnetic radiation is less than 500 picoseconds.

A method and apparatus for eliminating voids and improving crystal quality in shaped ceramic product, e.g. sapphire fiber or silicon sheet, from a melt by using a sloped die tip. The sloped die tip or array thereof comprises an outer sidewall which is sloped outwardly at an angle of 5° to 40° from the vertical.

The invention relates to a sapphire fiber-reinforced ceramic-matrix multi-phase composite as well as a preparation method and an application thereof. The preparation method comprises the steps as follows: a first component and a dispersing agent are mixed and are dried after being ball-milled under the protection of argon; the first component comprises iron oxide powder, aluminum powder and aluminum oxide powder; a dried product and a second component are evenly mixed, mixed powder is obtained, a sapphire fiber preform is arranged in the mixed powder, and hot-pressing sintering is performed under the vacuum condition; the second component comprises chromium powder; and a product obtained through hot-pressing sintering is pre-oxidized in the oxygen atmosphere, and the three-phase ceramic composite is obtained. With the three-phase ceramic composite, the mechanical strength of a heat shield prepared from the composite can be improved, the high-temperature resistance and the corrosion resistance of the heat shield can be improved, the service life can be prolonged, the thermal conductivity is reduced, and multi-cycle stable and reliable working can be realized at the high temperature of 1,900 K or above.

A method for fabricating a sensor includes coating an end-polished sapphire fiber with aluminum to produce a sapphire fiber having an aluminum coating, anodizing the aluminum coating to produce an aluminum oxide coating, and removing the aluminum oxide coating from a distal end of the sapphire fiber.

The invention provides a sapphire optical fiber temperature sensor using a separate probe, which is manufactured according to the following steps: design and manufacture the sensor's probe temperature-sensing black body cavity, heat-insulating protective sleeve and related installation accessories according to the specific conditions of the temperature-measured medium; assemble Probes; design and manufacture converters, which include optical filters, photoelectric conversion circuits, preamplifier circuits, two-stage amplifier circuits, analog signal conditioning circuits, voltage output circuits, power supply voltage stabilization circuits, and voltage conversion circuits; finally, use quartz transmission A fiber optic bundle connects the probe to the transducer. In the present invention, the blackbody cavity is separated from the sapphire optical fiber, and the sapphire optical fiber is not in direct contact with the temperature-sensitive blackbody cavity. During temperature measurement, the sapphire optical fiber is relatively far away from the high-temperature environment. The temperature is lower than its degradation temperature and still can transmit the blackbody radiation signal normally, so that the upper limit of the temperature measurement of the sensor reaches 2600 ℃.