Laser IInterferometric Dilatometer Applicable to Temperature Range from 1300 to 2000 K

A laser iInterferometric dilatometer has been developed for measuring the thermal expansion of high-temperature solids in the temperature range 1300 to 2000 K. The dilatometer consists of a double-path optical heterodyne iInterferometer, a spectral-band radiation thermometer, and a vacuum chamber with carbon- composite heaters. The performance of the dilatometer has been assessed on the basis of measurements of linear thermal expansion coefficients for glassy carbon. The relative standard deviation of the measured values from those calculated from the fitting polynomial is 0.630 over the temperature range investigated. The combined standard uncertainties in the measured values are estimated to be less than 1.30 over this range. The process of sample relocation predominantly affects the reproducibility of the experimental results.