以氢氧化镁和二氧化硅为主要原料,采用固相反应法合成了镁橄榄石,借助XRD、SEM、EDS等分析手段研究了热处理温度、组成变化对样品的物相组成、显微结构、基本物理性能等性质的影响.研究结果表明:镁橄榄石自1500 ℃开始大量形成,热处理温度升高有利于镁橄榄石的形成及长大;组成中富镁可以促进镁橄榄石、抑制顽火辉石生成,氧化镁迁移扩散在其颗粒表面析出镁橄榄石,并在其周围生长长大,晶粒圆润紧密生长;富硅时,先生成顽火辉石,然后在顽火辉石周围逐渐转化为镁橄榄石,形成的晶粒棱角分明,晶粒之间由富硅相组成.%Synthesis of forsterite by solid phase reaction was carried out with magnesium hydroxide and silica as the main raw materials. The effects of heat treatment temperature and composition on the phase composition, microstructure and basic physical properties of samples were investigated by means of X-Ray Diffraction, Scanning Electron Microscope and Energy Dispersive Spectroscopy. The results show that the forsterite starts to form in 1500 ℃, and the heat treatment temperature increase is favorable to the formation and growth of forsterite. The composition of magnesium-rich can promote the formation of forsterite and inhibit the formation of enstatite. After the diffusion of magnesia, the forsterite precipitates on the surface of the magnesium oxide particles, and grows in the surroundings, and the crystal grains grow smoothly and roundly. When the composition is silicon-rich, enstatite generate firstly, and then around the enstatite gradually transformed into forsterite, grains growth angular, and the composition between the grains is silicon-rich phase.
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