Improving the Adhesive Properties by Sandblasting the Surface with Copper Slag and Glass Beads

The aim of the research was to examine the effect of sandblasting the adherent surfaces on the shear strength of aluminium alloy-glass adhesive joints. An EN AW-1050A aluminium alloy and non-hardened soda-lime glass were used as samples. The sandblasting materials in the study were copper slag and glass beads. Due to the brittleness of the glass, an adhesive joint design was created to allow strength testing. The adhesive joints took the form of lap joints, where a glass sample was placed between two aluminium samples. The length of the glass sample corresponded to the length of the adhesive joint overlap. The bonding process of the glass samples was carried out in two stages in order to maintain the dimensions of the joint. The adhesive used in the test was a two-component epoxy adhesive prepared on the basis of bisphenol A and a polyamide curing agent mixed at a ratio of 80 g of curing agent per 100 g of epoxy resin. For each sandblasting agent, adhesive joints consisting of three variations of surface treatments were made: sandblasted aluminium alloy-sandblasted glass, sandblasted aluminium alloy-untreated glass, untreated aluminium alloy-sandblasted glass. The distance between the nozzle and treated surface was 10 ± 1 cm, and the pressure of sandblasting was 0.6 MPa. One sample of each material differing in surface preparation was selected for a topography analysis. The shear strength tests performed showed that sandblasting increased the strength of the adhesive joints of the glass and aluminium alloy. The highest strength was obtained for joints where both materials were prepared using copper slag sandblasting. This was confirmed through statistical analysis. Only for this type of joint, statistical significance relative to the other adhesive bonding variants was obtained.