Mechanical model of thrust force and torque in longitudinal-torsional coupled ultrasonic-assisted drilling of CFRP

• Published in: International journal of advanced manufacturing technology 2022-03, Vol.119 (1-2), p.189-202
• Main Authors: Ma, Guofeng, Kang, Renke, Yan, Chao, Bao, Yan, Zhu, Xianglong, Dong, Zhigang
• Format: Article
• Language: English
• Subjects: Advanced manufacturing technologies; Aircraft industry; Burrs; CAE) and Design; Carbon fiber reinforced plastics; Carbon fiber reinforcement; Chipping; Composite materials; Computer-Aided Engineering (CAD; Contact force; Corrosion fatigue; Corrosion resistance; Cutting force; Cutting parameters; Drilling; Engineering; Experiments; Extrusion; Fatigue life; Feed rate; Hand tools; Industrial and Production Engineering; Kinematics; Manufacturing; Material properties; Mechanical Engineering; Media Management; Model accuracy; Modelling; Original Article; Thrust; Titanium alloys; Torque; Vibration; Workpieces
• ISSN: 0268-3768; 1433-3015
• DOI: 10.1007/s00170-021-08192-y

Carbon fiber-reinforced plastic (CFRP) composites are increasingly utilized in the aircraft manufacturing field due to their excellent properties of high specific strength/modulus, good corrosion resistance, flexible designability, and long fatigue life. But CFRP composites belong to typical difficult-to-cut materials, and tearing, burrs, and delamination can easily occur in its drilling process. Longitudinal-torsional coupled ultrasonic-assisted drilling (LTC-UAD) is a promising technology to suppress the drilling defects of CFRP composites, and thrust force and torque are significant factors affecting the drilling quality of CFRP composites. In this paper, a mechanical model for predicting thrust force and torque in LTC-UAD of CFRP composites is presented in terms of the spindle speed, feed rate, ultrasonic parameters, tool geometry, and workpiece material properties. The oblique cutting modeling is used for the cutting lip, and the corresponding cutting region is divided into chipping region, pressing region, and bouncing region, respectively. The chisel edge is regarded as a rigid wedge-shaped body extruding into the workpiece material, and the contact theory is utilized to obtain the contact force between the chisel edge and the workpiece material. Furthermore, longitudinal and torsional vibrations are introduced into the modeling of cutting force by considering the dynamic feed angle and dynamic uncut chip thickness. The accuracy of the model is verified by the drilling experiments, and the results show that the predicted values of the thrust force and torque are in good consistency with the measured ones. The maximum deviations of the predicted thrust force and torque compared to the measured values are 13% and 11%, respectively.