高强度碳纤维增强复合材料层合板的钻削制孔过程及其缺陷形成分析

Study on Drilling Behaviors and Defects Forming Process of High-Strength CFRP Laminates

单向层合结构的高强度碳纤维增强树脂基复合材料已逐渐发展成为航空承力结构件的主要材料,相关的切削加工需求也越来越多。由于显著的各向异性,单向层合结构的碳纤维复合材料易在切削加工中形成缺陷,难切削加工性明显。针对T800级高强度CFRP单向层合材料开展直角自由切削试验,研究其在切削过程中的切削力和切削热随纤维方向角的变化产生的各向异性行为。针对制孔刀具三尖钻和八面钻开展CFRP层合板的钻削制孔试验,研究了三尖钻和八面钻的具体钻削过程中切削力、扭矩和切削温度的变化规律及其对钻削缺陷形成的影响。此外,对钻削制孔形成的孔壁加工表面进行分析,得到了典型孔壁缺陷的形貌照片并分析其形成原因。

High-strength carbon fiber reinforced polymer （CFRP） with unidirectional laminate structure has gradually developed into major material in load-bearing components in aerospace,and the cutting demand of CFRP is increasing.Because of the significant anisotropy,CFRP laminates highly tend to produce defects and are typical difficult-to-machine materials.Orthogonal cutting experiments on T800 high-strength CFRP unidirectional laminates are conducted to study the variation of cutting force,torque and cutting temperature with different fiber orientations.Based on the drilling experiments with brad point drill and multifacet drill,the effects of cutting force,torque and cutting temperature on defect forming process are discussed,and SEM topography of hole wall surface with typical defects is given.Through analyzing the wall surface of drilling holes,defect formation mechanism under different drilling processes is given.