Recession behavior of Yb_2Si_2O_7 phase under high speed steam jet at high temperatures

摘要

Recession behavior of Yb_2Si_2O_7 phase was examined under high speed steam jet environment between 1300℃ and 1500℃. Yb_2Si_2O_7 phase was formed on the bulk surface by the decomposition of Yb_2Si_2O_7 phase and the elimination of silica component at elevated temperatures. The phase ratio of Yb_2SiO_5/Yb_2Si_2O_7 increased up to 1400℃ and then decreased above 1400℃. The relative intensity of 220 peak for Yb_2Si_2O_7 phase increased with increasing the temperatures. Fine grains were generated on the bulk surface at 1300℃. The phase decomposition caused on the grain interior. A porous structure was formed on the bulk surface during the test at 1400℃. Surface cracks were generated for 1400℃ test sample. A smooth surface was generated on the surface of 1500℃ test sample. The triple points of the grains were bridged with a glassy phase.