A procedure for thermal expansion coefficient measurement is presented. A quartz dilatometer and a digital image processing technique were employed to obtain an accurate measure of the elongation of a prismatic specimen placed in a tubular furnace. By testing several symmetrically coated specimens the thermal expansion coefficient of a NiCoCrAlY-ZrO2(Y2O3) coating was obtained. The relationships for deducing the coefficient of the coating were derived by the multi-layer beam model and their sensitivity to experimental errors was discussed. Results were obtained in the range 20 degrees C-950 degrees C, both for the substrate and coating materials. An estimate of results accuracy is given, based on a Monte Carlo simulation of uncertainties.
Thermal expansion coefficient of a NiCoCrAlY-ZrO2(Y2O3)coating by a digital image processing based dilatometer
BEGHINI, MARCO;BERTINI, LEONARDO;FRENDO, FRANCESCO
2000-01-01
Abstract
A procedure for thermal expansion coefficient measurement is presented. A quartz dilatometer and a digital image processing technique were employed to obtain an accurate measure of the elongation of a prismatic specimen placed in a tubular furnace. By testing several symmetrically coated specimens the thermal expansion coefficient of a NiCoCrAlY-ZrO2(Y2O3) coating was obtained. The relationships for deducing the coefficient of the coating were derived by the multi-layer beam model and their sensitivity to experimental errors was discussed. Results were obtained in the range 20 degrees C-950 degrees C, both for the substrate and coating materials. An estimate of results accuracy is given, based on a Monte Carlo simulation of uncertainties.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
