A zirconia single-crystal fibre-optic sensor for contact measurement of temperatures above 2000 degrees C

Conventional sapphire fibre-optic sensors show excellent performance in hig h-temperature applications, but they cannot be used for contact measurement of temperatures above 1900 degrees C. In order to extend the operating tem perature of fibre-optic sensors, a radiation-based zirconia single-crystal fibre-optic sensor has been developed. This novel sensor can be operated up to 2300 degrees C. A 60 mm long and 0.45 mm thick yttria-stabilized zircon ia single-crystal fibre with one end coated with a layer of BeO ceramic is used to generate and transmit radiation signals at high temperature. Anothe r 520 mm long and 0.80 mm thick sapphire fibre is used as a sub-high-temper ature waveguide. Experimental results from 1200 degrees C to 2300 degrees C demonstrate that the developed sensor is very promising for applications b eyond 2000 degrees C.