CFRP减振镗杆设计与减振性能实验研究

Design and experimental study of CFRP vibration damping boring bar design and vibration damping performance

为了提升镗杆的减振能力,减少价格昂贵、难加工的硬质合金材料在减振镗杆中的使用,本文以碳纤维复合材料(Carbon Fiber Reinforced Plastics,CFRP)为主材设计出新型复合结构减振镗杆。在基于传统的使用模态仿真和切削实验方法优化镗杆结构的基础上,提出了新的优化途径,即从镗杆的频响函数中推导出镗杆的动刚度特性函数,根据该函数,以施加到镗杆上的动载荷频率为自变量、动刚度为因变量,通过动刚度曲线研究自变量变化时能够有效延缓镗杆动刚度减小的方法,研究发现,提升镗杆的静刚度和减小其质量在优化镗杆动刚度特性方面的效果更加突出。根据本文的研究结果对CFRP镗杆进行了参数优化和实验验证,结果表明,在中高速切削时,与硬质合金镗杆相比,优化后的CFRP镗杆在52%的切削速度范围内拥有更强的减振性能,可以在受到动载荷的情况下将自身的动刚度维持在较为稳定的水平,从而具备更好的减振能力。

To improve the vibration damping ability of the boring bar and reduce the use of expensive and difficult⁃to⁃process hard alloy materials in damping boring bar,a new type of vibration damping boring bar is designed using Carbon Fiber Reinforced Plastics(CFRP)as the main material.Based on the traditional methods of optimizing the boring bar structure using modal simulation and cutting experiments,a new optimization method is proposed.This method involves deriving the dynamic stiffness expression of the boring bar from its frequency response function.Based on this function,the variation of the independent variable,which is the frequency of the dynamic load applied to the boring bar,is studied through the dynamic stiffness curve.The aim is to find methods that effectively delay the reduction in dynamic stiffness as the independent variable changes.The research findings suggest that increasing the static stiffness of the boring bar and reducing its mass can effectively improve its dynamic stiffness.Based on the research results,the structural design parameters of the CFRP boring bar are optimized.Finally,the cutting experimental results demonstrate compared with carbide boring bars,CFRP boring bars exhibit stronger vibration damping performance with a cutting speed range of 52%.It can maintain its own dynamic stiffness at a relatively stable level when subjected to dynamic loads,thereby providing better vibration absorption capabilities.