目的 建立一种新的易碎空心微球抛光机模型，并研制出该样机，用于空心Be微球的精密抛光。方法 采用限位孔设计解决微球低应力夹持问题，添加不同数量的配重球，用于调整待抛球的滑动摩擦力大小和防止其飞出限位孔。上下盘偏心放置，实现微球无规运动。采用白光干涉仪分析抛光后Be微球的表面粗糙度。结果 抛光机模型计算表明，待抛球一直在做周期性的变速和变加速运动，其周期大小由上盘转动频率决定，变加速运动增加了微球的滑动摩擦成分，有利于提高微球抛光效率。此外，待抛球表面抛光轨迹呈现无规行走，这有利于抛光的均匀性。使用该原理抛光机，在24 h内能够将直径1.2 mm、均方根表面粗糙度510 nm的易碎铍（Be）靶丸抛光至85 nm。结论 理论和实验共同验证了易碎微球抛光机模型的合理性和可行性，上下盘放置方式、限位孔大小设计和配重球数量等关系着易碎微球的抛光均匀性和抛光效率。

To establish a new model of polishing machine for friable hollow capsule (invention patent ZL201510335040.6), and develop a prototype for the precise polishing of hollow Be capsules. The restriction hole design was used to solve the problem of low stress clamping of sphere. Different numbers of counterweight spheres were added to adjust the sliding friction force and prevent the spheres from flying out of the restriction hole. The upper and lower grinding pans were placed eccentrically to achieve random movement of the spheres. The surface roughness of the polished Be capsules was analyzed by white light interferometer. The model calculation shows that the unpolished spheres always roll periodically in the mode of variable speed and variable acceleration. The periodicity is determined by the rotation frequency of the top pan. The spheres of variable acceleration motion increase the sliding friction components and are beneficial to improving the polishing efficiency. In addition, the surface polishing trajectory presents random walk, which can ensure the polishing uniformity. The fragile beryllium (Be) capsule with a diameter of 1.2 mm and a root mean square surface roughness of 510 nm can be polished to 85 nm in 24 hours by this polishing machine. The rationality and feasibility of the fragile sphere polishing machine model are verified by both theory and experiment. The polishing uniformity and polishing efficiency of fragile spheres are closely related to the placement mode of upper and lower grinding pans, the size of restriction hole and the number of counterweight spheres.