Electret, piezoelectret and piezoresistivity discovered in steels, with application to structural self-sensing and structural self-powering

  title={Electret, piezoelectret and piezoresistivity discovered in steels, with application to structural self-sensing and structural self-powering},
  author={Xiang Xi and D. D. L. Chung},
  journal={Smart Materials and Structures},
  • Xiang XiD. Chung
  • Published 7 June 2019
  • Materials Science, Physics
  • Smart Materials and Structures
Electret, piezoelectret, piezoresistivity and stress-dependent electric permittivity are reported in unmodified steels. Structural stress/strain self-sensing based on piezoelectret/piezoresistivity is demonstrated under tension. Structural self-powering is shown by the electret’s inherent electric field, (2.224 × 10−5) V m−1 and (1.051 × 10−5) V m−1, and power density, 29.2 and 41.8 W m−3, for low carbon steel and stainless steel, respectively, being enabled by the electret’s electrical… 

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