基于高速铣削稳定性的减振工具系统基础研究及其应用

发布时间：2018-08-28 11:10

【摘要】：随着高速加工技术的普及与深入发展,切削加工过程中的颤振现象已成为制约零件加工效率、影响工件加工精度的一个重要因素。而被动式阻尼减振器具有减振效果良好、安装方便、结构简单等诸多优点,已逐渐运用于刀具系统的切削加工中,减振刀具和阻尼工具的研究及其工程应用正受到国内外制造业专家学者们的不断重视。本文基于铣削系统的动态切削力公式和颤振稳定性预测模型,设计外置式阻尼减振器并安装在刀杆上,研究了不同阻尼减振器的阻尼材料及其安装位置对其抑振效果的影响规律,深入分析了所设计的阻尼减振器对薄壁件切削过程中的颤振稳定性、切削力以及工件表面形貌的影响规律。本文的主要研究工作如下:(1)针对所设计的外置式阻尼减振工具系统,进行系统结构的有限元模态分析以及考虑外载荷的谐响应分析,讨论分析了阻尼减振器的材料以及安装位置对主轴——刀具系统的影响规律,仿真结果表明:当安装阻尼减振器后,系统的第1阶、2阶固有频率及其对应的共振幅值均逐渐降低,且刀尖处的响应位移也开始减小,其中,以45钢阻尼材料减振器的响应位移减小幅度最大,达到24%。当阻尼减振器的安装位置距离逐渐增大时,系统的第1阶、2阶固有频率逐渐降低,但其对应的共振幅值和响应位移均逐渐增加。(2)基于阻尼减振器的仿真模型搭建模态测试平台,采用冲击力锤进行单点激励,得到不同阻尼材料、不同减振器安装位置下系统的模态参数,其变化趋势和仿真结果基本一致,理论平均误差在2.5%以内,说明本文所构建的仿真模型基本正确,所建模型和仿真结果对开发减振工具系统具有一定的参考价值。(3)基于所设计的阻尼减振工具模型和装置,进行阻尼/无阻尼减振工具系统切削过程的颤振稳定性对比仿真,以及薄壁件切削试验,结果表明:阻尼减振工具系统能够提高最小临界切削深度达65%,有效降低切削过程中切削力峰值,提高零件表面加工质量。本文所设计的外置式阻尼减振器,可运用于铣削刀具和其他回转类切削刀具,丰富了被动式阻尼减振技术在刀具切削领域的运用,为抑制加工中的颤振现象提供了一个具体的研究思路,对于改善零件实际生产效率、提高零件加工表面质量具有重要意义。
[Abstract]:With the popularization and development of high-speed machining technology, the chatter phenomenon in cutting process has become an important factor that restricts the machining efficiency of parts and affects the machining accuracy of workpieces. The passive damping damper has many advantages, such as good damping effect, convenient installation, simple structure and so on, and has been gradually used in cutting machining of tool system. The research and engineering application of vibration absorbing tools and damping tools have been paid more and more attention by domestic and foreign manufacturing experts and scholars. Based on the dynamic cutting force formula and flutter stability prediction model of milling system, an external damping damper is designed and installed on the cutter rod. The influence of damping materials and installation positions of different damping absorbers on their vibration suppression effect is studied. The flutter stability of the designed dampers during the cutting process of thin-walled parts is deeply analyzed. The influence of cutting force and surface morphology of workpiece. The main work of this paper is as follows: (1) the finite element modal analysis of the system structure and the harmonic response analysis considering the external load are carried out for the designed external damping tool system. The material of damping damper and the influence of installation position on the spindle tool system are discussed and analyzed. The simulation results show that: when the damping damper is installed, The first and second order natural frequencies and their corresponding common amplitudes of the system are gradually decreased, and the response displacement at the tip of the tool is also decreasing. The response displacement of the 45 steel damping material absorber is the largest, reaching 24%. When the installation distance of damping damper increases gradually, the first and second order natural frequencies of the system decrease gradually, but the corresponding common amplitude and response displacement increase gradually. (2) the modal test platform is built based on the simulation model of damping absorber. The modal parameters of the system with different damping materials and different installation positions of shock absorbers are obtained by single point excitation with impact force hammer. The variation trend is basically consistent with the simulation results, and the theoretical average error is less than 2.5%. It shows that the simulation model constructed in this paper is basically correct, and the established model and simulation results have certain reference value for the development of vibration absorber tool system. (3) based on the designed damping tool model and device, The flutter stability of the damped / undamped vibration control tool system is compared and simulated, and the thin-wall cutting test is also carried out. The results show that the damping tool system can increase the minimum critical cutting depth to 65 and effectively reduce the peak value of cutting force in the cutting process and improve the machining quality of the parts surface. The external damping damper designed in this paper can be used in milling tools and other rotary cutting tools, which enriches the application of passive damping vibration absorption technology in the field of cutting tools. It provides a concrete research idea for restraining chatter phenomenon in machining. It is of great significance to improve the actual production efficiency of parts and improve the quality of machined surface.
【学位授予单位】：江苏大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG54

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