Kakovost lepilnega spoja med lesom in jeklom

The aim of the research was to determine the suitability of selected polyurethane and epoxy adhesives for structural bonding of wood and steel. We tested four polyurethane adhesives COSMO and two epoxy adhesives ERGO and XEPOX. The quality of the adhesive bond was evaluated by a shear strength test followed by one of the following exposure tests of the specimens: exposure to the standard climate with 65 % relative humidity and a temperature of 20 °C; exposure to humid climate with 87 % humidity and a temperature of 20 °C; and various exposures (soaking/cooking) in water. The results showed that the polyurethane adhesives studied in this work cannot compete with epoxy adhesives in terms of bonding quality. The epoxy adhesives provided excellent bonding properties in dry conditions, and proved to be potentially suitable for non-structural use in humid conditions. However, in order to use the selected adhesives in construction applications, it is recommended that the adhesive joint should be additionally reinforced with screws to ensure the reliability of the joint in the event of exceptional moisture or fire