【摘要】 采用Si粉直接氮化的方法制备氮化硅针状晶体 .通过热力学计算 ,选择了晶体生长的温度和压力范围 .探讨了温度、压力、添加剂等对针状晶体晶相、形貌、产率的影响 ,并在 1 850℃ ,CaO质量分数为 1 0 %条件下 ,制备了长径比为 4～ 1 0的 β -Si3N4 针状晶体 ,产率为 68% .采用XRD ,TEM ,SEM对得到的氮化产物及针状晶体进行了表征 .更多还原

【Abstract】 Elongated silicon nitride grains are prepared through nitridation process of silicon powders directly. The range of temperature and pressure associated with the acicular grain growth are obtained by thermodynamic calculation. The influence of temperature, pressure and additives on the crystal phase, morphology and yield rate of elongated Si₃N₄ grains is studied, also the elongated β-Si₃N₄ grains is prepared with yield rate at about 68% and aspect ratio in the range of 4 to 10（1 850 ℃, 10% CaO as additives）. The nitriding production and elongated silicon nitride grains are also characterized by XRD, TEM, SEM.更多还原