As a weight-reducing material in aerospace applications, carbon fiber reinforced polymer (CFRP) requires precision grinding to ensure the accuracy and assembly of mating positioning surfaces. However, achieving low-damage machining of CFRPs remains challenging. Flood cooling reduces the mechanical properties, while dry grinding deteriorates the surface integrity, making minimum quantity lubrication (MQL) a viable alternative. However, nanolubricants struggle to penetrate the grinding area due to gas barrier obstruction. Consequently, a new CFRP grinding approach using multiangle 2D ultrasonic vibrationempowered nanolubricant MQL was proposed. An analytical force model is crucial for optimizing machining strategies and adjusting parameters. The aim is to reveal grinding mechanics and develop a force model under different ultrasonic and lubrication-cooling conditions. First, a uniform random fiber distribution model and a grinding wheel model were established, and the mechanical properties of the interface were predicted. Then, the intermittent grinding behavior and dynamic stiffnesses of the multiangle 2D ultrasonic vibration-assisted grinding (UVAG) system were investigated based on the geometric kinematics of the grains' trajectory. Furthermore, based on the deformation deflection curve, bending fracture force models for 45°, 90°, and 135° fibers were established with different contact and boundary conditions. The material removal mechanisms of shear and tension-compression buckling in 0° CFRP grinding were revealed, and an elliptical contact normal force model was established. The interlayer shear in 45° CFRPs was analyzed. The longitudinal compressive matrix cracking and fiber shear fracture in the 90° CFRPs were elucidated. Fiber microbuckling and fiber bundle removal of 135° CFRPs were investigated. Finally, grinding force models with different fiber orientation angles (FOAs) were interconnected and experimentally assessed. Experimental assessments demonstrated that the grinding force model has acceptable estimation error and effectively captures the mechanics of CFRPs with different FOAs.

中文翻译：

---

超声赋能微量润滑磨削CFRP受力模型


作为航空航天应用中的减重材料，碳纤维增强聚合物（CFRP）需要精密磨削以保证配合定位面的精度和装配。然而，实现碳纤维增强塑料的低损伤加工仍然具有挑战性。淹没冷却会降低机械性能，而干磨则会恶化表面完整性，因此微量润滑 (MQL) 成为可行的替代方案。然而，由于气体屏障的阻碍，纳米润滑剂难以渗透研磨区域。因此，提出了一种使用多角度二维超声振动增强纳米润滑剂 MQL 的新 CFRP 磨削方法。分析力模型对于优化加工策略和调整参数至关重要。目的是揭示磨削力学并开发不同超声波和润滑冷却条件下的力模型。首先，建立了均匀随机纤维分布模型和砂轮模型，并预测了界面的力学性能。然后，基于颗粒轨迹的几何运动学，研究了多角度二维超声振动辅助磨削（UVAG）系统的间歇磨削行为和动态刚度。此外，基于变形偏转曲线，建立了不同接触和边界条件下45°、90°和135°纤维的弯曲断裂力模型。揭示了0°CFRP磨削中剪切和拉压屈曲的材料去除机制，并建立了椭圆接触法向力模型。分析了 45° CFRP 的层间剪切力。阐明了 90° CFRP 中的纵向压缩基体开裂和纤维剪切断裂。 研究了 135° CFRP 的纤维微屈曲和纤维束去除。最后，将具有不同纤维取向角（FOA）的磨削力模型相互关联并进行实验评估。实验评估表明，磨削力模型具有可接受的估计误差，并有效地捕捉了具有不同FOA的CFRP的力学特性。