Identification of bearing failure in composite-aluminium bolted joints using digital image correlation

Hannes Wemming a,b, Stefan B. Lindström b, Lars Johansson b, Zlatan Kapidžić a,b

a Saab AB, SE-581 88 Linköping, Sweden
b Division of Solid Mechanics, Department of Management and Engineering, Linköping University, SE-581 83 Linköping, Sweden

Keywords

CFRP-aluminium, Bolted joints, Digital image correlation (DIC), Bearing failure, Strain measurement

BACKGROUND

WORLD LEADING PRODUCT

Hannes Wemming, Saab Aeronautics, is dedicated to developing efficient methods for predicting the strength of bolted joints for an industrial application.

His latest released research article is of a large part built on data gathered through the use of the Image Systems TEMA DIC System – 

Identification of bearing failure in composite-aluminum bolted joints using digital image correlation 

was published on Composite Structures in 2022, and is kindly open to the public.

Follow the link below to read the full extent of his report:

linear Strain

TURN-KEY SOLUTION
  • Exx and Eyy in DIC results are clearly presenting the horizontal and vertical strain distribution around 2 bolt

Shear Strain

howland analytical strain vs DIC
  • Full field shear strain presenting vivid shear status around those 2 bolts during tensile test

Displacement

TURN-KEY SOLUTION
  • Full field displacment showing different values around the bolts
  • Displacement on the left side of the top bolt is significant larger than the value on the right side

Bending Effect

  • 3D visialization with magnification aspect ratio
  • Visible bending effect in TEMA DIC 3D diagram during the tensile test
  • Local material failure is indicated by permanent deformation of the composite material that bulges out near the bolt hole