Excessive damage increase in dual phase steels under high strain rates and temperatures

Cobanoglu M., Ertan R. K., ŞİMŞİR C., EFE M.

INTERNATIONAL JOURNAL OF DAMAGE MECHANICS, cilt.30, sa.2, ss.283-296, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 30 Sayı: 2
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1177/1056789520958053
  • Dergi Adı: INTERNATIONAL JOURNAL OF DAMAGE MECHANICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.283-296
  • Anahtar Kelimeler: Damage, dual phase, void, forming, dynamic strain aging, sheet, ANISOTROPIC DAMAGE, INITIATION, GROWTH, BEHAVIOR
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Damage formation in dual phase steels is a complex process and it may be sensitive to the deformation conditions and mechanisms. In this study, the damage parameter is measured and compared under quasi-static and industrial forming conditions (temperatures: 25 vs 200, 300 degrees C and strain rates: 10(-3)vs 10 s(-1)) for DP590 and DP800 steels. Resonance frequency and ultrasonic sound velocity techniques are utilized for the measurements to test the effectiveness and validity of each technique. At a given strain, the damage values can be up to 700% higher at industrial forming conditions, under which dynamic strain aging (DSA) controls the deformation behavior. DSA results in lower formability and is the likely mechanism responsible from the abnormal damage evolution. Measured damage parameters are also confirmed with the void fraction characterization by microscopy, which also provided details on the void shape and distribution with respect to the deformation conditions.