Precipitation of NbC and Hot Ductility of Austenitic Stainless Steels

• Ohmori Y.

  Central Research Laboratories, Sumitomo Metal Industries, Ltd.

• Maehara Y.

  Central Research Laboratories, Sumitomo Metal Industries, Ltd.

抄録

Effect of NbC precipitation on hot deformation of austenitic stainless steels has been studied with particular emphasis on ductility. The mechanism for reducing ductility in the temperature range where NbC precipitation occurs can also explain the surface cracking mechanism of continuously cast low alloy steel slabs. The ductility trough in slow strain rate tensile tests at around 1073 K in Nb-bearing steels is accompanied by the intergranular microvoid coalescence mode of fracture. This ductility loss is induced by rather coarse NbC particles precipitated on the grain boundaries, the precipitation free zones along the grain boundaries and the dynamic precipitation of fine NbC particles within the grains. That is, when an external stress is applied, the strain will be concentrated within the soft layers of precipitation free zones by the matrix strengthening due to fine dispersion of NbC. This will lead to the decohesion of the NbC/matrix interfaces on grain boundaries, resulting in the intergranular microvoid coalescence.

収録刊行物

• Transactions of the Japan Institute of Metals

  Transactions of the Japan Institute of Metals 25 (3), 160-167, 1984

  社団法人 日本金属学会

キーワード

• niobium-carbide
• hot deformation
• austenitic stainless steels
• surface cracking of continuously cast slab
• ductility trough
• slow straining
• intergranular ductile fracture
• precipitation free zone
• dynamic precipitation
• strain concentration

詳細情報

• CRID: 1390282680093477504
• NII論文ID: 130003486129
• DOI: 10.2320/matertrans1960.25.160
• ISSN: 24324701
• ISSN: 00214434
• Web Site: https://www.jstage.jst.go.jp/article/matertrans1960/25/3/25_3_160/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可