A shear thickening-chemical polishing (ST-CP) approach exploiting the recombination mechanism of shear-thickening and chemical-physical friction is proposed for ultraprecision machining of optical materials. The ST-CP slurries with dynamic rheological behaviour are characterized, and the optimal preparation process is explored for high-efficiency polishing of workpieces. A critical shear rate (CSR) prediction model in the flow field of slurries is systematically investigated and experimentally verified in detail. A mathematical control of the material removal rate (MRR) is modelled and developed for ST-CP. The shear-thickening-induced micro-cutting and chemical-physical friction contribute to the material removal mechanism in the ST-CP process. A special chemical reaction layer consisting of Li₂O and Nb₂O₇ evoked on the workpiece, which can soften the surface layer of lithium niobate (LiNbO₃), increases the chemical-physical friction and material removal through micro-cutting and shearing. The material removal process in ST-CP is a dynamic equilibrium process in which atoms of the workpiece surface are continuously involved to form new substances or oxides to achieve a soft chemical reaction layer, accompanied by the shear-thickening-induced micro-cutting action. A series of ST-CP experiments validate that the maximal error between theoretical and experimental data is less than 11.5%, which shows the high degree of accuracy of the MRR prediction model. Measurements and calculations are performed to explore the effects of shearing velocities, Al₂O₃ content, pH value, and oxidant content on surface roughness and MRR. When the shear-thickening induced micro-cutting and chemical reaction reach a dynamic equilibrium, a maximum MRR of up to 65.8 mg/h is achieved, and surface roughness is significantly reduced within 120 min from Ra 36.04 nm–1.46 nm with low subsurface damage (<5 nm). This investigation reveals that ST-CP is a progressive ultra-precision manufacturing approach for optical polishing and finishing of crystal materials.

提出了一种利用剪切增稠和化学-物理摩擦的复合机制的剪切增稠-化学抛光 (ST-CP) 方法，用于光学材料的超精密加工。表征了具有动态流变行为的 ST-CP 浆料，并探索了用于工件高效抛光的最佳制备工艺。系统地研究了泥浆流场中的临界剪切率 (CSR) 预测模型并进行了详细的实验验证。材料去除率 (MRR) 的数学控制是为 ST-CP 建模和开发的。剪切增稠引起的微切削和化学物理摩擦有助于 ST-CP 工艺中的材料去除机制。由 Li ₂ O 和 Nb组成的特殊化学反应层工件上产生的₂ O ₇可以软化铌酸锂（LiNbO ₃）表层，通过微切割和剪切增加化学物理摩擦和材料去除。ST-CP中的材料去除过程是一个动态平衡过程，其中工件表面的原子不断参与形成新的物质或氧化物，以实现柔软的化学反应层，并伴随着剪切增厚引起的微切削作用。一系列ST-CP实验验证，理论数据与实验数据最大误差小于11.5%，显示了MRR预测模型的高度准确性。进行测量和计算以探索剪切速度 Al _{2 的影响}O ₃含量、pH 值和氧化剂含量对表面粗糙度和 MRR 的影响。当剪切增稠引起的微切割和化学反应达到动态平衡时，最大 MRR 可达 65.8 mg/h，表面粗糙度在 120 分钟内从Ra 36.04 nm-1.46 nm显着降低，亚表面损伤低(<5 纳米)。该研究表明，ST-CP 是一种用于晶体材料光学抛光和精加工的渐进式超精密制造方法。