Thermal and offaxis behaviour of notched or damaged GLARE

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Thermal and off-axis behaviour of notched or
damaged GLARE
Ir. M. Hagenbeek

• Promoters
• Prof. dr. ir. R. de Borst
• Engineering Mechanics
• Dr. ir. A. Vlot
• Aircraft Materials
• External support
• Ir. C.G. van Hengel
• Structural Laminates Industries

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Contents

• Fiber Metal Laminates GLARE
• Fire resistance
• Unanswered questions
• Research objective
• Project tasks
• Ultimate goal

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Fiber Metal laminates GLARE

• GLARE, GLAss REinforced aluminium, consists of
  alternating layers of aluminium and glass fiber
  prepreg

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Fiber Metal Laminates GLARE

• GLARE build-up
• Aluminium layer thickness 0.2 - 0.3 - 0.4 - 0.5
  mm
• Fiber/adhesive layer build-up from multiple
  0.125 mm UD layers
• FM94 epoxy adhesive for structural bonding

• Standard grades
• Fiber/adhesive Fiber/adhesive
• layer thickness layer build-up
• GLARE 2A 0.25 mm 0/0
• GLARE 2B 0.25 mm 90/90
• GLARE 3 0.25 mm 0/90
• GLARE 4A 0.375 mm 0/90/0
• GLARE 4B 0.375 mm 90/0/90
• GLARE 5 0.5 mm 0/90/90/0

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Fiber Metal Laminates GLARE

• GLARE offers
• Damage tolerance
• fatigue
• impact
• corrosion
• Reduced weight
• Fire resistance

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Fire resistance
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Fire resistance
T 1150 0C, Heat flux 204 kW/m2
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GLARE on the A3XX

• GLARE will be applied in the upper fuselage

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Unanswered questions

• Combination of aluminium and glass-fibers in
  GLARE causes a complex thermal and mechanical
  behaviour
• Effect of off-axis loading conditions have not
  been studied extensively for GLARE
• Effect of temperature on aluminium, glass-fibers
  and epoxy matrix interaction is not well
  understood
• Internal stresses, shear at the edges and
  material behaviour around holes, notches or
  damage need closer investigation

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Unaswered questions

• What is the effect of temperature and off-axis
  loading on the internal stresses around a notch?

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Research objective

• Investigation and modeling of the
• thermal and off-axis behaviour of
• notched or damaged GLARE

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Project tasks

• Finite Element Modeling and Analysis
• Extention of the finite element developed by
  Joris Remmers to include temperature dependency
  of material parameters, thermal loading and heat
  flux input
• Analysis of thermal and off-axis effects for
  GLARE
• Development of a Design Tool
• Calculation and optimization of material
  properties of existing GLARE and future
  laminates, including plasticity effects, thermal
  loading and residual stresses
• Research and Tests
• Investigation of temperature and off-axis effects
  for basic material properties of GLARE

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Ultimate goal

• Will we be able to avoid fire disasters in
  future?
• Can we calculate and improve the fire resistance
  and structural integrity in case of post-crash
  fires?

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Questions?