Non-isothermal crystallization kinetics of mineral wool fibers

作者：Tang Xu Long; Zhang Mei^*; Guo Min; Zhang Zuo Tai; Wang Xi Dong

来源：Journal of University of Science and Technology Beijing, 2011, 33(12): 1523-1528.

• Activation energy of crystallization
• Avrami exponent
• Crystalline phasis
• Crystallization behavior
• Crystallization mechanisms
• DTA curves
• Exothermic peaks
• Kissinger methods
• Nonisothermal crystallization kinetics
• Ozawa method
• Surface crystallization
• XRD

The crystallization behavior of mineral wool was investigated by means of differential thermal analysis (DTA) and X-ray diffraction (XRD). DTA curves reveal the presence of two overlap exothermic peaks and XRD results shows that two crystalline phases are separated out: one is akermanite-gehlenite (AlCa2Mg0.5O7Si1.5), which was crystallized between 850°C and 920°C; the other is anorthite (CaAl2Si2O8), which was crystallized between 880°C and 1 010°C. The Ozawa method and the modified Kissinger method were used to analyze the crystallization mechanism and the activation energy of crystallization. For the crystalline of akermanite-gehlenite, the activation energy of crystallization and the Avrami exponent are 248 kJ&middotmol-1 and 0.682 respectively, indicating surface crystallization; whereas for anorthite, the activation energy of crystallization is 347 kJ&middotmol-1, revealing three-dimensionality of crystal growth according to the results of scanning electron microscopy (SEM).

• 出版日期2011
• 单位北京科技大学; 北京大学