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利用XRD、FT-IR、Raman、SEM-EDS等方法研究了CaO·SiO2在低钙高温烧结过程的晶体结构、生成动力学和微观组织.当反应物CaCO3和SiO2摩尔比为1.0时,加热过程中优先生成2CaO·SiO2,然后2CaO·SiO2进一步与SiO2反应生成CaO·SiO2;烧结过程中不会生成3CaO·2SiO2和3CaO·SiO2.升高反应温度和延长保温时间有助于2CaO·SiO2向CaO·SiO2转化,并使烧结产物的拉曼光谱特征峰发生一定的蓝移和宽化.在1400℃ 烧结1 h时CaO·SiO2在烧结产物的含量能够达到97.4％.CaO·SiO2的生成动力学遵循二级化学反应模型,相应的反应表观活化能和指前因子分别为505.82 kJ/mol和2.16×1014s?1.“,”The crystal structure, formation kinetics and micro-morphology of CaO·SiO2 during high-temperature sintering process were studied in low-calcium system by XRD, FT-IR, Raman and SEM-EDS methods. When the molar ratio of CaCO3 to SiO2 is 1.0, β-2CaO·SiO2 forms firstly during the heating process, and then CaO·SiO2 is generated by the transformation reaction of pre-formed 2CaO·SiO2 with SiO2. 3CaO·SiO2 and 3CaO·2SiO2 do not form either in the heating or sintering process. Rising the sintering temperature and prolonging the holding time promote the phase transition of 2CaO·SiO2 to CaO·SiO2, resulting in the sintered products a small blue shift and broadening in Raman spectra. The content of CS can reach 97.4％ when sintered at 1400 ℃ for 1 h. The formation kinetics of CaO·SiO2 follows the second-order chemical reaction model, and the corresponding apparent activation energy and pre-exponential factor are 505.82 kJ/mol and 2.16×1014 s?1 respectively.