基于矫顽效应的钽酸锂高效超精密磨削加工研究

To meet the requirements of high efficiency ultra-precision machining of Lithium tantalate (LT) and to address the challenges of surface cracks or damage induced by internal stress which are resulted from reverse piezoelectric effect and thermal expansion, we propose a novel ultra-precision grinding method based on coercive field effect. The spontaneous polarization is obviously suppressed with the application of external reverse electric field, reverse thermal field and high electrical conductivity electrolyte solution, and make the strength of rest internal electric field recover to zero, The cracks induced by electrical field and thermal field are also obviously retrained and the machining efficiency is also improved. Through theoretical analysis, numerical simulation and experiment research, we intend to reveal the broken mechanism and establish the internal electric field model of machining process for LT; Explore the key process parameters of quantify control based on the coercive field effect; Research the influence of process parameters on the machining of LT and the removal mechanism of LT under the coercive field effect; The project develop a novel machining method which is contributed in high efficiency and high quality surface for LT and also has a scientific sense and engineering application value in enriching the precision and ultra-precision machining technology .

面向钽酸锂高效超精密加工需求，针对其因压电逆效应产生的内应力及热膨胀而引起的表面裂纹甚至破损的难题。本项目提出一种基于“矫顽效应”的高效超精密磨削加工方法。通过施加外加反向电场、反向热场和高电导率磨削液等方法来抑制极化现象，使得剩余内电场极化强度恢复到零，进而防止由于加工产生的电场、热场引起的加工裂纹，提高加工的成品率。本项目通过理论分析、数值模拟和实验研究，揭示钽酸锂材料破损机理，建立钽酸锂加工过程中内电场模型，探索基于“矫顽效应”的定量控制的关键工艺参数，研究各工艺参数对于钽酸锂加工的影响规律以及钽酸锂在“矫顽效应”下的材料去除机理。本项目为钽酸锂提供了一种高效超精密加工新方法，同时对于丰富精密超精密加工技术也具有重要的科学意义和工程应用价值。

针对钽酸锂高效超精密加工中因压电逆效应产生的内应力及热膨胀而引起的表面裂纹甚至破损的难题。本项目提出一种基于“矫顽效应”的高效超精密磨削加工方法。通过施加外加反向电场、反向热场和高电导率磨削液等方法来抑制极化现象，使得剩余内电场极化强度恢复到零，进而防止由于加工产生的电场、热场引起的加工裂纹，提高加工的成品率。本项目通过理论分析、数值模拟和实验研究，揭示钽酸锂材料破损机理，建立钽酸锂加工过程中内电场模型，探索基于“矫顽效应”的定量控制的关键工艺参数，研究了针对钽酸锂加工的固结磨具，研究各工艺参数对于钽酸锂加工的影响规律以及钽酸锂在“矫顽效应”下的材料去除机理，最终实现了6寸钽酸锂晶片厚度100微米以下超精密磨削。