Adhesive properties of epoxy resin with chromic hardener

Cohesive and adhesive properties have been compared of epoxy resins crossli nked either with chromic-based hardener or with conventional amine-type har dener. Higher cohesive parameters, such as yield strength, Young's modulus and impact resistance were observed for the material cured with chromic har dener. The adhesive strength of metal-metal joints (steel-aluminium) has be en also found to be higher for chromic hardener containing epoxy compared t o conventional curing systems. The time dependencies of adhesive strength a fter thermal treatment at 140 degreesC of the joints showed a higher therma l resistance of the epoxy with chromic hardener when compared to the amine cured resin.