Stress redistribution around fiber breaks in unidirectional steel fiber composites considering the nonlinear material behavior

SABUNCUOĞLU B., MUTLU Ç., KADIOĞLU F. S., Swolfs Y.

COMPOSITE STRUCTURES, cilt.239, 2020 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 239
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1016/j.compstruct.2020.111959
  • Dergi Adı: COMPOSITE STRUCTURES
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Steel-fiber composites, Stress concentrations, Large deformation, Finite element analysis
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

The use of steel fibers as reinforcement in polymer composites is recently increasing thanks to their ductility, high stiffness and wide range of diameters. Unlike carbon and glass fibers, steel fibers often end up with a non-circular cross-section due to their manufacturing technology. This may influence the stress redistribution around fiber breaks, which is important in longitudinal tensile failure of unidirectional composites. A parametric study was performed by using 3D finite element models with randomly distributed and oriented hexagonal fibers. Rather than the fiber shape, the distance between fibers was shown to have an influence on stress concentrations in terms of both average and peak stress concentrations. The plastic behavior of steel fibers resulted in smaller stress concentrations and faster stress recovery whereas the opposite was observed for the plastic behavior of epoxy. For different strain levels, results were shown to depend on the relative stiffness of steel and epoxy in the plastic region.