号数 | ばね論文集 65 号（ 2020 年） |

ページ数 | pp.101-108 |

種類 | 論文 |

論文名 | 直交異方性および極異方性コイルばね中の表面き裂の応力拡大係数 |

Title | Stress Intensity Factors for Semi-elliptic Surface Cracks in Compression Coil Springs with Orthotropic Anisotropy and Those with Cylindrical Anisotropy |

著者 | 中曽根 祐司^{1)}，村主 和憲^{2)} |

Author | Yuji NAKASONE^{1)},Kazunori MURANUSHI^{2)} |

抄録 | |

Abstract | This study has made 3D finite element analyses on the stress intensity factors for semi-elliptic surface cracks in compression coil springs of cylindrically anisotropic and orthotropic materials in order to clarify the effects of the anisotropies on the correction factors Fi （i=I, II and III）for the three modes of the stress intensity factors. The cylindrical anisotropy was modeled by the stiffness tensor composed of the same components as those of the orthotropic material plus the additional C45 component. In the cylindrically anisotropic coil springs, the mode-I correction factor FI was dominant being the order of 0.7-0.9 around the periphery of the cracks. As the C45 value increased, the FI value decreased around the periphery of the cracks except for the vicinity of the wire surface. The absolute values of FII and FIII, however, increased locally beyond 1. In the orthotropic coil springs, FI was also dominant being the order of 0.9. The absolute values of the other correction factors remained less than 0.2 and reached the highest value in the vicinity of the wire surface. Not only the values but also the istributions of the three kinds of correction factors around the crack periphery in the orthotropic coil springs were found not so different from those of the semi-elliptic surface cracks in the isotropic compression coil springs. |

著者の所属 | 1)東京理科大学 2)元東京理科大学大学院生 |

Belonging | 1)Tokyo University of Science 2)Former Graduate Student, Graduate School, Tokyo University of Science |

Key Words | Compression Coil Spring, Orthotropy, Cylindrical Anisotropy, Drawing, FEM |