高速度工具鋼の疲労挙動への窒素の効果 Effect of Nitrogen on Fatigue Behavior of a High-Speed Steel

この論文にアクセスする

この論文をさがす

著者

抄録

  Ultra-sonic fatigue tests were carried out for W-Mo type high-speed steel specimens containing 40 ppm N (low N), 160 ppm N (middle N) and 400 ppm N (high N). The fatigue strength of the high-N specimen was lower than those of the low-N and middle-N specimens, which were nearly identical. The increase in N content caused no changes in average sizes of MC carbides, M<sub>6</sub>C carbides and carbides consisting of M<sub>6</sub>C and MC (M<sub>6</sub>C•MC), but increased the size of large MC carbides, such as the maximum size from about 6.5 μm to 13 μm. The fracture origin of the high-N specimen was coarse MC carbides of about 13 μm, and those of the low-N and middle-N specimens were large aggregates of about 12 μm, consisting of two or three M<sub>6</sub>C•MC carbides. Voids formed by decohesion of the M<sub>6</sub>C/MC interfaces in M<sub>6</sub>C•MC carbides larger than about 5 μm in the low-N, middle-N and high-N specimens, and those formed by destruction of MC carbides larger than about 8 μm in the high-N specimen were observed after fatigue fracture under a stress amplitude of 1100 MPa. This result arises because of greater stress concentration due to more inhomogeneous deformation around the MC and M<sub>6</sub>C•MC carbides develops as the sizes of both the carbides increase. In the high-N specimen, cracking was initiated from the voids in coarse MC carbides, while in the low-N and middle-N specimens, a crack propagated between two voids in adjacent large M<sub>6</sub>C•MC carbides which constitute a carbide aggregate. The fatigue strength of the high-N specimen is lower because the nucleation of the cracks from coarse MC carbides occurs more rapidly than that of the cracks in large M<sub>6</sub>C•MC carbide aggregates of the same size as the coarse MC carbides.<br>

収録刊行物

  • 日本金屬學會誌 = Journal of the Japan Institute of Metals

    日本金屬學會誌 = Journal of the Japan Institute of Metals 72(2), 105-110, 2008-02-01

    The Japan Institute of Metals

参考文献:  16件中 1-16件 を表示

被引用文献:  1件中 1-1件 を表示

各種コード

  • NII論文ID(NAID)
    10021149674
  • NII書誌ID(NCID)
    AN00062446
  • 本文言語コード
    JPN
  • 資料種別
    ART
  • ISSN
    00214876
  • NDL 記事登録ID
    9371281
  • NDL 雑誌分類
    ZP41(科学技術--金属工学・鉱山工学)
  • NDL 請求記号
    Z17-314
  • データ提供元
    CJP書誌  CJP引用  NDL  J-STAGE 
ページトップへ