项目名称: NiFe2O4/Nano-TiN陶瓷基惰性阳极微结构分形特征及热应力研究
项目编号: No.51504177
项目类型: 青年科学基金项目
立项/批准年度: 2016
项目学科: 矿业工程
项目作者: 杜金晶
作者单位: 西安建筑科技大学
项目金额: 20万元
中文摘要: NiFe2O4陶瓷基惰性阳极有助于减少温室气体、碳氟化合物和沥青烟气的排放,减轻当前环境负荷。但其脆性高、抗热震性差等问题限制了它的实际应用。因此,从微观尺度出发,针对该材料热冲击后结构的形貌特征、阳极高温服役环境下温度场分布特征和热应力演变机制开展研究十分必要。本项目对合成NiFe2O4/Nano-TiN陶瓷基惰性阳极的烧结行为进行研究,揭示阳极材料的合成机制。利用分形法对阳极微结构进行刻画,采用盒计维数法计算阳极裂纹及断口形貌的分形维数,建立分形维数与热冲击临界温差和剩余强度间的定量关系。通过扩展有限元模拟NiFe2O4/Nano-TiN阳极结构的传热行为,建立温度分布云图。对阳极结构热应力进行模拟,建立力学结构模型,计算阳极结构的热应力和热变形,阐明阳极热应力场和应变分布特征,为实现大尺寸、抗热震NiFe2O4陶瓷基惰性阳极的制备提供理论依据和技术支持,助力于铝电解工业的可持续发展。
中文关键词: NiFe2O4陶瓷基阳极;纳米TiN;微结构;分形特征;热应力
英文摘要: NiFe2O4-based inert anodes can help to decrease the emission of greenhouse gas, fluorocarbons and asphalt fumes and alleviate the present environmental load. However, high brittleness and unsatisfactory thermal shock resistance are still the obstacles, limiting the practical application of NiFe2O4-based composite anodes. Thus, basic research about morphology characteristics of structure after thermal shock, temperature distribution characters and evolution mechanism of thermal stress at the micro-scale level needs to be carried out necessarily. After studying on the sintering behavior of preparing NiFe2O4/Nano-TiN based ceramic anodes, the synthesis mechanism of the ceramic composite anodes will be revealed. Through the fractal characterization of microstructure after thermal shock and fractal dimensional calculation of cracks and fracture surface with Box-counting method, the quantitative relationship between the fractal dimension and thermal shock critical temperature difference, statistical residual strength of the composite anode will be established. Through simulation of heat transfer behavior for NiFe2O4/Nano-TiN based anode structure with extended finite element, the temperature field cloud chart of anode structure will be obtained. Besides, through modeling study on the structure thermal stress, establishing model of the mechanical structure, calculation of thermal stress and deformation, characteristics of thermal stress and strain distribution will be clarified. This will provide theoretical basis and technical support for manufacturing large-sized NiFe2O4 ceramic anodes with better thermal shock resistance, which will contribute to sustainable development of aluminum electrolysis industry.
英文关键词: NiFe2O4 ceramic anodes;Nano-TiN;Micro-structure;Fractal feature;Thermal stress