Surface treatment of carbon steel for glue joints

Abstract

Presented paper is devoted to the study of strength of adhesive joints glued by epoxide or acrylate glue. Plain carbon steel with different surface pretreatment was joined by glues and then was test single lap shear joint strength. In case of insufficient (or none) surface pretreated plain carbon steel decrease strength of these glue joints. The research indicated the influence of steel surface treatment before glue bonding with epoxy adhesives to adhesion strength of bonded joints after corrosion affects. Corrosion affects were simulated in the condensing chamber with the presence of SO2. Results show that sufficient surface treatment for joining by epoxy glue is perfect cleaning and roughening of surface. Decrease strength of glue joints is explain by production of oxidic (corrosion) layers. These layers have an effect of weak layer. These weak layers decrease of loading capacity of glue joint. As suitable pretreatment was found etching in phosphoric acid.