Pore Forming Mechanism of Forsterite Insulation Materials Synthesized by Molten Salt Method

Abstract:

Abstract. The forsterite thermal insulation materials were synthesized by molten salt method with forsterite and NaCl-Na₂CO₃ salt, sintered at 1000°C, 1050 °C, 1100°C and 1150°C respectively. Studying complex pore structures is the key to understand the mechanism of pore-forming. The mechanism of the variation in the heterogeneous pore structure was analyzed based on differential thermal analysis, thermogravimetry, high-pressure mercury intrusion porosimetry and scanning electron microscope. The results show that the NaCl-Na₂CO₃ salt play the role of promoting sintering in liquid environment at high temperature as well as forming pore as placeholder. The mechanism of pore-forming contains three parts: the pores < 6.6 μm are mainly formed by sodium carbonate decomposition under high temperature and vapor pressure; the forming way of 6.6~66μm derives from carbonate decomposition and salt evaporate jointly; The salt stay in the slender and curved space shaped by the rearrangement of forsterite particles, forms the pore diameter of > 66 μm after salt dissolves in water.

• Periodical: Key Engineering Materials (Volume 697)
• Pages: 134-137
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.697.134
• Online since: July 2016
• Authors: Yun Fei Song, Cheng Ji Deng, Hong Xi Zhu, Jun Ding
• Keywords: Forsterite, Mechanism, Molten Salt, Particle Size

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