Ultrasonic cutting with a disc cutter is an advanced machining method for the high-quality processing of Nomex honeycomb core.The machining quality is influenced by ultrasonic cutting parameters,as well as tool orient...Ultrasonic cutting with a disc cutter is an advanced machining method for the high-quality processing of Nomex honeycomb core.The machining quality is influenced by ultrasonic cutting parameters,as well as tool orientations,which are determined by the multi-axis machining requirements and the angle control of the cutting system.However,in existing research,the effect of the disc cutter orientation on the machining quality has not been studied in depth,and practical guidance for the use of disc cutters is lacking.In this work,the inclined ultrasonic cutting process with a disc cutter was analyzed,and cutting experiments with different inclination angles were conducted.The theoretical residual height models of the honeycomb core,as a result of the lead and tilt angles,were established and verified with the results obtained by a linear laser displacement sensor.Research shows that the residual height of the honeycomb core,as a result of the tilt angle,is much larger than that as a result of the lead angle.Furthermore,the tearing of the cell wall on the machined surface was observed,and the effects of the ultrasonic vibration,lead angle,and tilt angle on the tear rate and tear length of the cell wall were studied.Experimental results revealed that ultrasonic vibration can effectively decrease the tearing of the cell wall and improve the machining quality.Changes in the tilt angle have less effect than changes in the lead angle on the tearing of the cell wall.The determination of inclination angles should consider the actual processing requirements for the residual height and the machining quality of the cell wall.This study investigates the influence of the inclination angles of a disc cutter on the machining quality of Nomex honeycomb core in ultrasonic cutting and provides guidelines for machining.展开更多
以直刃尖刀超声辅助切割Nomex蜂窝芯的简化模型为基础,建立基于脆性断裂力学理论的超声辅助切削动态力模型,并分情况讨论了刀具与材料间的相对运动关系。分析指出在不同振幅条件下,材料的切割破坏存在断续和连续两种形式,进而推导了切...以直刃尖刀超声辅助切割Nomex蜂窝芯的简化模型为基础,建立基于脆性断裂力学理论的超声辅助切削动态力模型,并分情况讨论了刀具与材料间的相对运动关系。分析指出在不同振幅条件下,材料的切割破坏存在断续和连续两种形式,进而推导了切割过程中的切削力的理论公式。其中超声振幅、刀具前倾角、进给速度和超声频率等参数对材料切削力大小均有影响。在理论分析的基础上,开展了超声辅助切割Nomex蜂窝芯复合材料实验。试验结果表明,进给方向的超声振幅和刀具前倾角对切削力的影响较大:当进给方向的超声振幅从0到15μm变化、刀具前倾角从15°到45°变化时,切削力均可降低70%~80%;进给速度和超声频率对于切削力影响较小:当进给速度从500到6000 mm/min变化12倍时,切削力仅变为1.5倍;超声频率35 k Hz与15 k Hz相比,切削力降低10%~30%。试验结果与理论分析结论一致。展开更多
基金The authors are grateful to the financial support from the National Natural Science Foundation of China(Grant No.U20A20291)the National Key R&D Program of China(Grant No.2019YFA0708902).
文摘Ultrasonic cutting with a disc cutter is an advanced machining method for the high-quality processing of Nomex honeycomb core.The machining quality is influenced by ultrasonic cutting parameters,as well as tool orientations,which are determined by the multi-axis machining requirements and the angle control of the cutting system.However,in existing research,the effect of the disc cutter orientation on the machining quality has not been studied in depth,and practical guidance for the use of disc cutters is lacking.In this work,the inclined ultrasonic cutting process with a disc cutter was analyzed,and cutting experiments with different inclination angles were conducted.The theoretical residual height models of the honeycomb core,as a result of the lead and tilt angles,were established and verified with the results obtained by a linear laser displacement sensor.Research shows that the residual height of the honeycomb core,as a result of the tilt angle,is much larger than that as a result of the lead angle.Furthermore,the tearing of the cell wall on the machined surface was observed,and the effects of the ultrasonic vibration,lead angle,and tilt angle on the tear rate and tear length of the cell wall were studied.Experimental results revealed that ultrasonic vibration can effectively decrease the tearing of the cell wall and improve the machining quality.Changes in the tilt angle have less effect than changes in the lead angle on the tearing of the cell wall.The determination of inclination angles should consider the actual processing requirements for the residual height and the machining quality of the cell wall.This study investigates the influence of the inclination angles of a disc cutter on the machining quality of Nomex honeycomb core in ultrasonic cutting and provides guidelines for machining.
文摘以直刃尖刀超声辅助切割Nomex蜂窝芯的简化模型为基础,建立基于脆性断裂力学理论的超声辅助切削动态力模型,并分情况讨论了刀具与材料间的相对运动关系。分析指出在不同振幅条件下,材料的切割破坏存在断续和连续两种形式,进而推导了切割过程中的切削力的理论公式。其中超声振幅、刀具前倾角、进给速度和超声频率等参数对材料切削力大小均有影响。在理论分析的基础上,开展了超声辅助切割Nomex蜂窝芯复合材料实验。试验结果表明,进给方向的超声振幅和刀具前倾角对切削力的影响较大:当进给方向的超声振幅从0到15μm变化、刀具前倾角从15°到45°变化时,切削力均可降低70%~80%;进给速度和超声频率对于切削力影响较小:当进给速度从500到6000 mm/min变化12倍时,切削力仅变为1.5倍;超声频率35 k Hz与15 k Hz相比,切削力降低10%~30%。试验结果与理论分析结论一致。
