Potential Influences of Impurities on Properties of Recycled Carbon Steel

• Daigo Ichiro

  Graduate School of Engineering, The University of Tokyo

• Tajima Keijiro

  Graduate School of Engineering, The University of Tokyo

• Hayashi Hideo

  Tokyo Metropolitan Industrial Technology Research Institute

• Panasiuk Daryna

  Graduate School of Engineering, The University of Tokyo

• Takeyama Kentrao

  Graduate School of Engineering, The University of Tokyo

• Ono Hideki

  Faculty of Sustainable Design, Academic Assembly, University of Toyama

• Kobayashi Yoshinao

  Institute of Innovation Research, Tokyo Institute of Technology

• Nakajima Kenichi

  National Institute for Environmental Studies, Japan

• Hoshino Takeo

  Graduate School of Engineering, The University of Tokyo

Abstract

Contamination with tramp elements is a major concern in steel recycling. This study aimed to identify the influence of impurity elements on the major properties of carbon steel. The content of impurity elements in recycled steel was determined via elemental analysis of randomly sampled steel bars. Of the 23 impurity elements considered, 15 were found to be mixed in the recycled steel. Industrial standards stipulate that the six major properties of carbon steel are tensile strength, elongation, yield point or proof stress, soundness in the welding area, fracture toughness, and bendability. The influence of the fifteen impurity elements on all of these properties except bendability was investigated by reviewing previous academic reports. Properties related to strength and stress were found to be enhanced by the presence of almost any impurity, while elongation and welding soundness were often compromised. The influence of impurities on the other properties remains largely unknown. The negative effects of impurities on the workability and weldability can be minimized by adjusting the steelmaking, casting, and annealing processes, or rethinking the design of products and manufacturing processes. Further, the incorporation of impurities may be prevented during the recovery of steel scrap from end-of-life products. A useful approach to the prevention of the negative influence of impurities is a new concept termed R-PSPP, which stands for recovery, process, structure, property, and performance.

Journal

• ISIJ International

  ISIJ International 61 (1), 498-505, 2021-01-15

  The Iron and Steel Institute of Japan

Keywords

• tramp elements
• recycled steel
• degradation
• R-PSPP
• carbon steel properties

Details

• CRID: 1390568456352929536
• NII Article ID: 130007969916
• DOI: 10.2355/isijinternational.isijint-2020-377
• ISSN: 13475460
• ISSN: 09151559
• Web Site: https://www.jstage.jst.go.jp/article/isijinternational/61/1/61_ISIJINT-2020-377/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed