The growing use of structural adhesives in aerospace and automotive for assembly lightweight materials is due to a series of advantages like a more uniform load in the joint and the absence of corrosion. Moreover, the substrate to be bonded often needs treatments for realising a reliable bonding. In fact, the quality of a bonded joint depends on the chosen surface treatment for the adherends. Industrial treatments for bonding like grit blasting and sanding are not repeatable processes. The use of a CO2 laser source allows removing the first surface layer of the matrix in a selective way and without damaging the underlying fibres. In this way, it is possible to design the surface texturing in order to maximize its performance and its processing time. The aim of this work consists in the development of a numerical model to predict the influence of the laser treatment on the mechanical strength of the bonded joint. The experimental results show that the use of this technology allows obtaining mechanical resistances of End Notched Flexure (ENF) bonded joints higher than 80% compared to untreated ones.
A new approach to increase the performances of bonded CFRP joints by laser texturing
Luca Sorrentino;Costanzo Bellini;Gianluca Parodo
2019-01-01
Abstract
The growing use of structural adhesives in aerospace and automotive for assembly lightweight materials is due to a series of advantages like a more uniform load in the joint and the absence of corrosion. Moreover, the substrate to be bonded often needs treatments for realising a reliable bonding. In fact, the quality of a bonded joint depends on the chosen surface treatment for the adherends. Industrial treatments for bonding like grit blasting and sanding are not repeatable processes. The use of a CO2 laser source allows removing the first surface layer of the matrix in a selective way and without damaging the underlying fibres. In this way, it is possible to design the surface texturing in order to maximize its performance and its processing time. The aim of this work consists in the development of a numerical model to predict the influence of the laser treatment on the mechanical strength of the bonded joint. The experimental results show that the use of this technology allows obtaining mechanical resistances of End Notched Flexure (ENF) bonded joints higher than 80% compared to untreated ones.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
