非均匀介质超声铣削系统振动特性研究  

Vibration Characteristics of the Longitudinal-torsional Composite Inhomogeneous Media Ultrasonic Milling System

作　　者：张存鹰[1,2] 赵波 ZHANG Cunying;ZHAO Bo(School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo 454000;College of Intelligent Manufacturing and Automation,Henan University of Animal Husbandry and Economy,Zhengzhou 450046)

机构地区：[1]河南理工大学机械与动力工程学院,焦作454150 [2]河南牧业经济学院智能制造与自动化学院,郑州450046

出　　处：《机械工程学报》2019年第19期221-232,共12页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51475148,U1604255)

摘　　要：采用纵扭复合超声振动铣削进行加工时,由于加工中心等空间受限场合对超声振动系统的尺寸限制,利用四分之一波长理论设计集换能器和复合变幅杆为一体的非均匀介质超声振动变幅系统,在变幅杆部分设计螺旋槽结构实现纵扭共振,并研究纵扭模态转换理论。对非均匀介质变幅系统进行有限元分析,仿真结果表明纵振系统固有频率理论值与仿真值接近,偏差仅为0.245%;对螺旋槽结构进行仿真发现槽深对其对超声变幅系统固有频率、扭纵幅值比例影响较大,螺旋角的影响次之,槽宽影响最小,振动系统测试实验表明固有频率和扭纵幅值比的仿真结果与实验结果变化趋势一致。分别对TC4钛合金和C/C碳纤维进行纵扭超声振动铣削和传统铣削实验对比,结果显示相对于传统铣削,在纵扭超声振动铣削加工中两组材料表面粗糙度值Ra分别下降78%和47%。纵扭复合非均匀介质超声振动铣削系统结构简单紧凑、振动幅值和方向可控性较好,采用纵扭超声振动铣削能有效提高工件表面加工质量。The material is processed by the longitudinal-torsional(L-T)composite ultrasonic vibration milling. Due to the size limitation of the ultrasonic vibration system, the 1/4 wavelength theory is used to design the inhomogeneous media ultrasonic variable amplitude system with the combination of the transducer and the composite horn. Longitudinal-torsional resonance is realized by designing spiral grooves on the horn, and the modal transformation theory of L-T vibration is analyed. The finite element analysis of the L-T composite inhomogeneous media ultrasonic variable amplitude system is studied. The simulation results show that the theoretical value of the natural frequency is close to the simulation value. The deviation is only 0.245%. The performed analysis of helical grooves structural characteristics reveal that the depth has great influence on the natural frequency and the amplitude ratio of the torsional-longitudinal, the influence of the helical angle is second, and the width has the smallest effect on the system performance. The test experimental data of the natural frequency and torsional-longitudinal amplitude ratio have the same trend with the simulation results. Through the comparison of two machining experiments with and without L-T ultrasonic vibration, the results show that the surface roughness values of TC4 and C/C carbon fibre in the L-T ultrasonic vibration milling are dropped by 78% and 47%. The structure of L-T inhomogeneous media ultrasonic vibration milling system is compact, which vibration amplitude and direction can be controlled reliably, meanwhile, the L-T composite ultrasonic vibration milling can effectively improve the workpiece surface processing quality.

关 键 词：纵扭复合振动 超声铣削 非均匀介质 螺旋槽 扭纵幅值比 表面质量 

分 类 号：TH6[机械工程—机械制造及自动化]