TY - JOUR
T1 - Bond durability of CFRP laminates-to-steel joints subjected to freeze-thaw
AU - Yang, Yongming
AU - Silva, Manuel A. G.
AU - Biscaia, Hugo
AU - Chastre, Carlos
N1 - The first author would like to thank Prof. Xian Guijun of Harbin Institution of Technology for providing the HIT CFRP laminates. The third author is also grateful to UNIDEMI and to Fundação para a Ciência e Tecnologia for the partial funding of this study under the Strategic Project PEst-OE/EME/UI0667/2014 and post-doctoral grant SFRH/BPD/111787/2015 , respectively.
PY - 2019/3/15
Y1 - 2019/3/15
N2 - The degradation mechanisms of bonded joints between CFRP laminates and steel substrates under severe environmental conditions require more durability data and studies to increase the database and better understand their causes. Studies on bond properties of double-strap CFRP-to-steel bonded joints with two different composite materials as well as adhesive coupons subjected to freeze-thaw cycles for 10,000 h were conducted to reduce that gap. In addition, the equivalent to the number of thermal cycles and their slips induced in the CFRP laminates was replicated by an equivalent (mechanical) loading-unloading history condition imposed by a static tensile machine. The mechanical properties of the adhesive coupons and the strength capacity of the bonded joints were only slightly changed by the artificial aging. It was confirmed that the interfacial bond strength between CFRP and adhesive is critically related to the maximum shear stress and failure mode. The interfacial bond strength between adhesive and steel degraded with the aging. However, the equivalent thermal cyclic bond stress caused no detectable damage on the bond because only the interfacial elastic regime was actually mobilized, which confirmed that pure thermal cycles aging, per se, at the level imposed, have a low impact on the degradation of CFRP-to-steel bonded joints.
AB - The degradation mechanisms of bonded joints between CFRP laminates and steel substrates under severe environmental conditions require more durability data and studies to increase the database and better understand their causes. Studies on bond properties of double-strap CFRP-to-steel bonded joints with two different composite materials as well as adhesive coupons subjected to freeze-thaw cycles for 10,000 h were conducted to reduce that gap. In addition, the equivalent to the number of thermal cycles and their slips induced in the CFRP laminates was replicated by an equivalent (mechanical) loading-unloading history condition imposed by a static tensile machine. The mechanical properties of the adhesive coupons and the strength capacity of the bonded joints were only slightly changed by the artificial aging. It was confirmed that the interfacial bond strength between CFRP and adhesive is critically related to the maximum shear stress and failure mode. The interfacial bond strength between adhesive and steel degraded with the aging. However, the equivalent thermal cyclic bond stress caused no detectable damage on the bond because only the interfacial elastic regime was actually mobilized, which confirmed that pure thermal cycles aging, per se, at the level imposed, have a low impact on the degradation of CFRP-to-steel bonded joints.
KW - Adhesive
KW - CFRP-steel bonded joints
KW - Durability
KW - Freeze-thaw
KW - Thermal stress
UR - http://www.scopus.com/inward/record.url?scp=85059815763&partnerID=8YFLogxK
U2 - 10.1016/j.compstruct.2019.01.016
DO - 10.1016/j.compstruct.2019.01.016
M3 - Article
AN - SCOPUS:85059815763
SN - 0263-8223
VL - 212
SP - 243
EP - 258
JO - Composite Structures
JF - Composite Structures
ER -