Comparison of novel surface treatments of Al 2024 alloy for al/cfrp adhesive bonded joints


Özgür Bora M. Ö. , ÇOBAN O. , AKMAN E. , Oztoprak B. , KUTLUK T.

INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES, cilt.103, 2020 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 103
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1016/j.ijadhadh.2020.102721
  • Dergi Adı: INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES

Özet

The objective of this study is to investigate the effect of silane and fiber laser treatments on the shear strength and failure type characteristic ofAA2024-T3/unidirectional carbon fiber-reinforced epoxy composite [0](8) laminates (Al/CFRP) adhesively bonded joints. Epoxy-based paste 2 part adhesive (Loctite EA 9396 AERO) was used for adhesive joining. Chemical surface treatment was tested with three different silane concentrations (1, 3 and 5 vol %) applied to AA2024-T3 aluminum plates after cleaning. In addition, 50 W pulsed fiber laser was used to AA2024-T3 aluminum plates for laser treatment. For determining the optimum fiber laser parameters (laser power, frequency and scanning speed) L9 orthogonal array Taguchi method (3 variables and 3 levels) was used. The chemical composition of the fiber laser and silane treated AA2024-T3 sample's was analyzed using Fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR). Shear strength values of the Al/CFRP bonded joints were determined by using single lap shear tests. From the test results, the silane concentration of 3 vol% on AA2024-T3 aluminum plates had a significant effect on shear strength of Al/CFRP bonded joints (16.44 MPa) compared to untreated samples (6.46 MPa). In addition, it was determined that the laser treating parameters of scanning speed of 100 mm/s, frequency of 80 kHz and power of 50 W laser power achieved the optimum surface of AA2024-T3 to be strongly bonded with CFRP (23.68 MPa). After mechanical tests, failure modes were also observed by using the digital camera.