【摘要】 大尺寸超硬陶瓷球体因优异的力学性能与耐磨特性，广泛应用于高端精密轴承和关键传动系统。然而，陶瓷球体的硬脆特性及尺寸效应使得在其研磨加工过程中难以兼顾球体形状精度与表面质量。针对这一问题，提出一种基于非对称变曲率研磨的超硬陶瓷球体高效超精密制造技术，通过改善研磨迹线覆盖均匀度和时效来提高大尺寸陶瓷球的加工精度和效率。首先，基于多点接触运动学原理，建立球体研磨迹线覆盖的数学模型，系统地分析V形导向槽几何构型对陶瓷球体材料去除均匀性的影响规律。随后，设计并制作了3种典型导向槽研磨盘，通过对比试验研究它们对不同尺寸球体的研磨性能。试验结果表明，当球体直径减小至41.21 mm以下时，传统旋转对称导向槽的研磨性能显著下降，而非对称变曲率导向槽在整个尺寸范围内均保持较高的研磨覆盖均匀度与稳定的材料去除率，从而实现了球形误差与表面粗糙度的更优控制。最后，采用非对称变曲率研磨技术和优化工艺参数制备了直径41.20 mm的氮化硅陶瓷球，其球形误差优于130 nm，表面粗糙度低于6 nm。所提非对称变曲率研磨技术为大尺寸高精度陶瓷球的高效超精密制造提供了理论依据与技术方法。更多还原

【Abstract】 Large-size superhard ceramic balls are increasingly employed in high-end precision bearings and critical transmission systems, owing to their superior mechanical properties and wear resistance. However, their high hardness, brittleness, and size effect make it difficult to simultaneously achieve high form accuracy and excellent surface quality during grinding. To address this challenge, this study proposes an efficient ultra-precision manufacturing technology for ceramic balls based on asymmetric variable-curvature grinding, which is designed to improve the uniformity of grinding trajectory coverage and also enhance machining efficiency. A mathematical model of grinding trajectory coverage is first established based on multi-point contact kinematics, and the influence of the V-groove geometry on the material removal uniformity of ceramic balls is systematically analyzed. Three typical groove-structured grinding plates are then designed and fabricated, with which comparative experiments are conducted to investigate their grinding performance under varying ball diameters. The results indicate that when the ball diameter decreases below 41.21 mm, the grinding performance of the conventional rotationally symmetric groove declines significantly, whereas the asymmetric variable-curvature grooves maintain high coverage uniformity and stable material removal, thereby ensuring superior control of sphericity error and surface roughness. Finally, a sphericity error better than 130 nm and a surface roughness below 6 nm are achieved for silicon nitride ceramic balls with a diameter of 41.20 mm, by the proposed asymmetric variable-curvature grinding technology together with optimized process parameters, which provides theoretical and technical support for the efficient ultra-precision manufacturing of high-precision large-size ceramic balls.更多还原