Influence of high heating rates on the adhesive properties
(2008)Abstract
The major disadvantage of using structural adhesives is the rate of strength formation during the bonding process. Welding and mechanical joining provide self-fixturing in seconds while most structural joints need minutes to days. A common possibility to reach a high initial strength of the bond is to precure or cure the bond via electromagnetic heating. Unfortunately not all structural adhesives can be heated up with high heating rates. As a result of the high heating rates the adhesives can be thermal damaged or froth up. The paper shows the latest results in terms of the influence of fast curing on adhesive properties. Tested adhesives were an epoxy resin, a polyurethane and two acrylate resins. Depending on the chemical adhesive composition the system can be cured fast. Analysing the adhesive in respect of their potential for a fast curing processes the DSC is able to give in a short time significant data of the stability of the system under high heating rate. Furthermore the paper shows the influence of different fast curing processes on the mechanical and thermo-mechanical properties.