Nickel-based single crystal superalloy is widely used in the field of aerospace and nuclear reaction equipment due to its good properties. Ultra-precision machining technology is an important means to ensure the surface quality of parts. However, the anisotropy of materials has great influence on the evolution of surface and subsurface defects and the removal of materials in the process of machining. In this paper, The MD (molecular dynamics) modeling and simulation verification of cutting anisotropic nickel-based single crystal superalloy workpiece with silicon nitride tool is carried out by using the mixed potential function simulation. Through cutting simulation and visualization, the types, number, deformation area and dislocation evolution of the machined surface defects and inside of the workpiece defect of nickel-based single crystal superalloy with different crystal orientations are analyzed. The evolutionary mechanism of the machined surface defects and the law of material removal are discussed. The research content provides a theoretical basis for parameter optimization and improvement of machining quality in the atomic and close-to-atomic scale (ACS) cutting process, and technical support for efficient and precise machining process of the nickel-based superalloy.

镍基单晶高温合金由于其良好的性能而广泛用于航空航天和核反应设备领域。超精密加工技术是保证零件表面质量的重要手段。然而，材料的各向异性对加工过程中表面和表面下缺陷的发展以及材料的去除有很大的影响。本文利用混合势函数模拟方法进行了氮化硅刀具切削各向异性镍基单晶高温合金工件的MD（分子动力学）建模和仿真验证。通过切割模拟和可视化，类型，数量，分析了不同晶向的镍基单晶高温合金的加工表面缺陷和加工缺陷内部的变形面积和位错演化。讨论了机械加工表面缺陷的演变机理和材料去除规律。研究内容为在原子尺度和接近原子尺度（ACS）切削工艺中参数优化和提高加工质量提供了理论基础，为镍基高温合金的高效，精密加工工艺提供了技术支持。