CFRP旋转超声辅助钻削的缺陷抑制 机理及实验研究

针对碳纤维增强树脂基复合材料（CFRP）在普通切削（CD）过程中因切削力及扭矩较大而产生的分层撕裂、孔壁纤维损失等缺陷，采用了旋转超声辅助钻削（RUAD）制孔方法。首先，分析了CFRP CD的孔缺陷类型及产生机理，并结合超声振动加工的特性，给出了RUAD的孔缺陷抑制机理。然后，搭建了包含非接触式感应供电旋转超声振动系统、立式加工中心和测力系统的实验平台。最后，在相同的工艺参数下，对比了CD和RUAD两种工艺下的切削力和扭矩、孔缺陷及孔壁质量。实验结果表明:相对CD，RUAD的切削力和扭矩分别降低41.46%~46.32%和41.61%~48.94%，且CFRP孔出入口及孔壁分层撕裂、纤维损失等缺陷得到了有效抑制，极大地改善了CFRP的钻孔质量。实验结果有效地验证了CFRP钻孔缺陷产生机理及超声振动抑制机理的正确性，RUAD可以用于CFRP低损伤制孔。 

Defect suppression mechanism and experimental study on rotary ultrasonic-assisted drilling of CFRP

To solve the delamination, tearing and fiber losing of carbon fiber reinforced plastic (CFRP) hole induced by large cutting force and torque during conventional drilling (CD), the rotary ultrasonic-assisted drilling (RUAD) technology is introduced. Firstly, based on the analysis of the types and forming mechanism of CFRP hole defects in CD and the characteristics of RUAD, the defect suppression mechanism of CFRP hole in RUAD is proposed. Then, the experimental platform including a self-designed contactless energy transfer and a vibration system for RUAD, vertical machining center platform and force measurement system is built. Finally, the cutting force and torque, hole defects and quality of hole wall obtained in both CD and RUAD are compared at the same process parameters, respectively. The experimental results indicate that compared with CD, the cutting force and torque produced in RUAD decrease by 41.46% to 46.32% and 41.61% to 48.94%, respectively. And the delamination, tearing and fiber losing of the CFRP hole are effectively suppressed and the hole quality is greatly improved. The forming mechanism of hole defects in CD and the defect suppression mechanism of CFRP hole in RUAD are verified to be correct by the experimental results. The research in this paper indicates that the RUAD process can be used for machining of CFRP hole with lowdamage.