Laser Surface Pre-Treatment of CFRP for Adhesive Bonding in Consideration of the Absorption Behaviour

Laser-based surface preparation of composite laminates leads to improved electrodes for electrical measurements

“…In photochemical ablation, the bond excitation above a certain limit induce material dissociation. This process is characteristic of lasers with short wavelengths, such as UV lasers [19]. At longer wavelengths, the applied energy is not high enough to induce the photolytic process and hence is absorbed into the material as vibrational energy or heat.…”

“…At longer wavelengths, the applied energy is not high enough to induce the photolytic process and hence is absorbed into the material as vibrational energy or heat. When the temperature reaches the vaporization temperature of the material, the material evaporates or sublimates [19]. Extensive surface modifications occur only when the applied energy reaches a certain threshold, which depends on the target material as well as the selected laser processing parameters.…”

Effect of an Atmospheric Pressure Plasma Treatment on the Mode I Fracture Toughness of a Co-Cured Composite Joint

“…For example, adhesion to carbon-fibre/bismaleimide [5], carbon-fibre/ polyether ether ketone (PEEK) [6,7], glass-fibre/nylon 6,6 [8], glass-fibre/polyester [9] and carbon-fibre/epoxy [10,11,12,13,14] composites have all been improved through the use of plasma treatments. However, careful selection of the processing parameters is required as too long a treatment can be detrimental to the joint strength [12,15].…”

A qualitative, process-parameter-based model for the release agent transfer during CFRP-part production: an approach to increase the initial bondability

“…After the crosslinking reaction of the resin-system and the demolding of the parts, release agent residues are found on the parts surface as several times shown (e.g. [6][7][8][9]). This indicates a release agent transfer during the production of the parts.…”

“…Within industrial applications, the challenge of the relatively bad initial bondability is solved by an additional process step-the bonding pre-treatment. Even if there are different approaches, like a laser [8] or plasma [9] application, which allow a sufficient and potentially automated bonding pre-treatment, it is still an additional process step which lowers the production efficiency.…”