Casting a beady eye on cars: structural adhesives are used in the bonding of automotive components, but poor dispensing can lead to incomplete curing and scrapping of parts. Dr Yorkgitis shows how glass beads can improve the mixing process. (Epoxies).

European Adhesives & Sealants (Surrey, UK), December, 2002 by Elaine Yorkgitis

Automakers are dramatically increasing their use of two-part (2K) structural adhesives, especially in body closure bonding. They have realised benefits in the assembly of closure panels by taking advantage of the more robust performance and longer shelf life of these 2K structural adhesive products.

But two-part adhesives depend upon on-ratio mixing to achieve these benefits, and the traditional manual mix ratio checking method does not provide enough information for total process control.

Ford has developed a patented system that enables adhesive mixing to be monitored in real time as it is dispensed. Eventually, the same technique is expected to permit nondestructive validation of bonds.

The new system `tags' one component of a 2K adhesive with...