Recession behavior of Lu2SiO5 under a high speed steam jet at high temperatures

Study of recession behavior of Lu2SiO5 bulk was performed in high speed steam jet with a velocity of similar to 50 m/s temperature range between 1300 and 1500 degrees C for 100 h. X-ray results showed that no phase change was observed for all samples after steam exposure. Detailed scanning electron microscopy examinations showed some cracks formation was observed on the bulk surface for the samples of 1400 and 1500 degrees C. Also, porous structure was formed on the bulk surface for the samples of 1300 and 1400 degrees C. As for 1500 degrees C sample, the porous structure disappeared after exposure test. The high magnification images of 1300 degrees C sample showed the depletion of grain boundary glassy phase. However, for 1400 degrees C sample, boundary phase was formed again, and the grain growth can be identified for the sample of 1500 degrees C. The recession mechanism can be explained by a mass transfer of evaporated species from the bulk surface and the weight loss rate measured can be expressed by Arrhenius plot. (C) 2011 Elsevier Ltd and Techna Group Sri. All rights reserved.