The surface integrity of a machined component influences its performance. For a fibre-reinforced polymer (FRP) composite, fragments in machining can be pushed into fractured surfaces, causing difficulties in the integrity examination experimentally. This paper presents a new numerical characterization method with the verification of microstructural examinations experimentally. Both conventional cutting and vibration- assisted cutting of unidirectional FRP composites with different fibre orientations were investigated. It was found that the new approach is convenient to show the fibre/matrix fracture and fibre–matrix debonding. The application of the method also revealed that fibre orientation significantly influences the final surface topography and subsurface damage, and that the vibration-assisted cutting can largely minimise the subsurface damage. When fibre bending or fibre crushing dominates the fracture of fibres in cutting, the method showed the surface roughness and subsurface damage of the machined FRP composite decreases with increasing the fibre orientation, and that the surface quality is the best when the fibres are aligned in the cutting direction.

机加工部件的表面完整性会影响其性能。对于纤维增强聚合物（FRP）复合材料，机加工中的碎屑可能会推入断裂的表面，从而在实验中难以进行完整性检查。本文提出了一种新的数值表征方法，并通过实验对微观结构进行了验证。研究了具有不同纤维取向的单向FRP复合材料的常规切割和振动辅助切割。结果发现，这种新方法可以方便地显示出纤维/基体的断裂和纤维-基体的剥离。该方法的应用还表明，纤维取向会显着影响最终表面形貌和亚表面损伤，并且振动辅助切割可以最大程度地减少表面下的损坏。当在切割过程中纤维弯曲或纤维破碎占主导地位时，该方法表明，加工后的FRP复合材料的表面粗糙度和亚表面损伤随着纤维取向的增加而降低，并且当纤维在纤维束中排列时，表面质量最佳。切割方向。