Scholarlink

<p>The slender and thin-walled boring cutters due to low dynamic stiffness and the rotational effect are prone to the occurrence of chatter vibration, resulting&#xa0;in unstable&#xa0;operation. To eliminate or suppress chatter, the present paper proposes a theoretical model consisting of a spinning thin-walled boring bar made of composite materials subjected to multiple working conditions. The hygrothermal strain is firstly included into the constitutive&#xa0;relation of the viscoelastic composite material based on the Love-type shell theory; the kinetic and potential energies are derived by combining with the Halpin–Tsai model for the carbon nanomaterials (CNs). By considering the hybrid virtual works of the regenerative force, internal and external damping forces as well as the flowing cutting fluid, the partial differential equations (PDEs) are obtained by utilizing the extended Hamilton’s principle. The PDEs are discretized to&#xa0;yield the ordinary differential equations (ODEs) based on quasi-Galerkin’s technique in conjunction with boundary conditions. The stability of the boring system is predicted by using both the semi-discrete method and Floquet theory. The accuracy and convergence of the present model are validated. Thereafter, the detailed numerical cases are performed. The results show that CNs, carbon fibers, geometrical and technological parameters as well as hygrothermal factors have considerable influence on the stability behavior. Moreover, damping induced by them can lead to changes in critical and supercritical speeds of the composite bar. It is demonstrated that the proposed model can be appreciably applied to a cantilever spinning boring bar to improve its machining performance.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Dynamic stability of a CNTs-reinforced composite thin-walled boring bar considering supercritical region

  • 期刊论文

  • 发表日期：

    2025年6月7日

查看全文
  • Jinfeng Zhang,
  • Xiaohui Yang,
  • Shuo Wang,
  • Chao Feng,
  • Yongsheng Ren,
  • Peisi Zhong,
  • Xiaolong Cao

摘要

The slender and thin-walled boring cutters due to low dynamic stiffness and the rotational effect are prone to the occurrence of chatter vibration, resulting in unstable operation. To eliminate or suppress chatter, the present paper proposes a theoretical model consisting of a spinning thin-walled boring bar made of composite materials subjected to multiple working conditions. The hygrothermal strain is firstly included into the constitutive relation of the viscoelastic composite material based on the Love-type shell theory; the kinetic and potential energies are derived by combining with the Halpin–Tsai model for the carbon nanomaterials (CNs). By considering the hybrid virtual works of the regenerative force, internal and external damping forces as well as the flowing cutting fluid, the partial differential equations (PDEs) are obtained by utilizing the extended Hamilton’s principle. The PDEs are discretized to yield the ordinary differential equations (ODEs) based on quasi-Galerkin’s technique in conjunction with boundary conditions. The stability of the boring system is predicted by using both the semi-discrete method and Floquet theory. The accuracy and convergence of the present model are validated. Thereafter, the detailed numerical cases are performed. The results show that CNs, carbon fibers, geometrical and technological parameters as well as hygrothermal factors have considerable influence on the stability behavior. Moreover, damping induced by them can lead to changes in critical and supercritical speeds of the composite bar. It is demonstrated that the proposed model can be appreciably applied to a cantilever spinning boring bar to improve its machining performance.