Enhancement of impact toughness of 0.05% P doped high strength steel through formation of an ultrafine elongated grain structure

Meysam Jafari, Yuuji Kimura, Yihong Nie, Kaneaki Tsuzaki

Research output: Contribution to journalArticle

5 Citations (Scopus)


An ultrafine elongated grain (UFEG) structure with a strong 〈110〉//rolling direction (RD) fibre deformation texture was produced by warm calibre-rolling at 773 K in 1 200MPa-class medium-carbon low-alloy steels with phosphorous (P) contents of 0.001 and 0.053 mass%. Charpy impact tests were performed at room temperature on the UFEG structure along with a conventional quenched and tempered (QT) structure. P segregation embrittlement completely disappeared in the UFEG structure. The UFEG structure exhibited the same high absorbed energy of 150 J regardless of P content, although the absorbed energy of the QT structure was significantly decreased from 93 J for 0.001 % P steel to 23 J for 0.053% P steel due to occurrence of intergranular fracture. The high absorbed energy of 150 J for 0.053% P-doped UFEG structure was believed to be due to both delamination fracture and fine/deep ductile dimples. The present results emphasized that the detrimental effects of P grain boundary segregation can be suppressed and the upper shelf energy can be increased through the formation of the UFEG structure.

Original languageEnglish
Pages (from-to)1660-1665
Number of pages6
Journalisij international
Issue number11
Publication statusPublished - Dec 1 2010
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

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