Gluing of Carbon Fiber Composite to Aluminum

  • For gluing the carbon fiber and aluminium, the 3M SCOTCH-WELD constructional glues are recommended. These are epoxy-type glues:
Type 1 9323 Red, very high thermal performance, high strength properties also in 80 ºC (23,4 N/mm2), especially for Al-gluing, the hardest of the three.
Type 2 7838 Yellow, high thermal performance, high strength properties, more elastic type glue
Type 3 2216 Grey, the most elastic glue type


  • Final hardening of these glue types can be carried out at elevated temperatures (see separate specifications)

Correct surface treatment and cleanliness in gluing process

For Aluminum profiles:

Acetone cleaning shot blasting → (Al2O3 / EKW36) → Acetone cleaning → Primer treatment (Dow-Corning Silane Z-6040)

For Carbon fiber composites:

Acetone cleaning → Shot blasting (Al2O3 / EKW36) → Acetone cleaning

Recommendations for each glue


  • Be careful not to damage composite when roughening, mechanical roughening can be used as alternative (e.g. abrasive paper 240 grit). Exel can also supply profiles with peel-ply textured surface
  • We recommend glue layer thickness s=0,15mm, this may need to be adjusted for design reasons (follow glue manufacturers recommendations)
  • For marine applications ensure no contact between carbon fiber and aluminum to avoid corrosion problems

3M specification sheets are available upon request. Other glue manufacturers epoxy glues can be used e.g. Ciba, Araldite, Loctite, Mega Metal etc.

These are general recommendations. Always follow glue manufacturers further recommendations and good engineering practice. Exel can not accept any responsibility or liability, direct or consequential, for loss or damage caused as a result of our recommendations. © Exel Oyj 1997