Low-Temperature Micro-Fracture Toughness Testing of Grain Boundaries in Steel

• Shimada Yusuke

  NIPPON STEEL CORPOLATION

• Harada Kosei

  Kumamoto University, Department of Materials Science and Engineering

• Mine Yoji

  Kumamoto University, Department of Materials Science and Engineering

• Yoshimura Masahide

  NIPPON STEEL CORPOLATION

• Takashima Kazuki

  Kumamoto University, Department of Materials Science and Engineering

抄録

Temper embrittlement in high-strength steel occurs due to the segregation of impurity elements along prior austenite (γ) grain boundaries, resulting in a decrease in intergranular strength. However, the grain boundary properties have not yet been experimentally investigated. In this study, we developed a micro testing method to selectively process micro-cantilever specimens based on a specific prior γ-grain boundary to measure the grain boundary fracture toughness. Fracture toughness tests using micro-cantilever specimens with side grooves and notch were carried out at 183 K and brittle fracture behavior was successfully obtained. The fracture surface showed almost flat and brittle crack propagation along the prior γ-grain boundary. The derived fracture toughness value, K_Q, is lower than that from previous values. By employing this method for the evaluation of intergranular fractures in steel, we believe that we can evaluate more intrinsic prior γ-grain boundary properties compared with conventional methods.

収録刊行物

• MATERIALS TRANSACTIONS

  MATERIALS TRANSACTIONS 62 (4), 570-573, 2021-04-01

  公益社団法人 日本金属学会

キーワード

• prior austenite grain boundary
• micro bend test
• brittle fracture
• fracture toughness
• low temperature

詳細情報

• CRID: 1390287462798620160
• NII論文ID: 130008002813
• NII書誌ID: AA1151294X
• DOI: 10.2320/matertrans.mt-m2020364
• ISSN: 13475320
• ISSN: 13459678
• NDL書誌ID: 031359283
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I031359283
• Web Site: https://www.jstage.jst.go.jp/article/matertrans/62/4/62_MT-M2020364/_pdf
• 本文言語コード: en
• データソース種別:
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  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
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