Abstract:
The research presents the behavior of the mechanical properties of epoxy adhesives & adhesively bonded single lap joints made using same epoxy adhesives (LY-556 /AD 22962). Research has shown that various factors impact the overall strength of epoxy adhesives & adhesively bonded single lap joints and their strength can be improved through various techniques and processes. One of the effective methods is addition of filler material to adhesive. Cork powder is a versatile natural raw material and being used as a crack stopping filler for enhancing the strength of adhesives & adhesively bonded single lap joints. However, this behavior of cork powder changes with change in filler concentration. Present study is focused on observing the variation in mechanical properties of epoxy adhesive & adhesively bonded single lap joints at different temperatures and different concentrations of cork powder and their effect on mechanical properties of adhesives & adhesively bonded single lap joints. An experimental investigation is conducted to study the strength of LY-556 epoxy adhesives & adhesively bonded single lap joints with Aluminum 5052 adherends at different temperatures and different cork filler concentration. The adhesives & single lap joints are tested under tensile testing at ultimate testing machine. The temperature ranges from 25 degrees, 50 degrees, 75 degrees and 100 degrees and the cork powder concentration for each temperature are 0.25wt.%, 0.5wt.%, 0.75wt.% and 1wt.%. It is observed that for different temperature and for each concentration, the strength of adhesives reflects an increase in toughness with addition of cork powder while overall tensile strength & modulus decreases with increase in cork powder & temperature. Single lap joints shows similar behavior trend so that he highest failure strength is observed at room temperature and at 0.5wt.% cork powder concentration and minimum strength is observed at 100 degrees (close to glass transition temperature) and at 1wt.% concentration. The type of failure is changes from mix mode failure to cohesive failure as temperature and cork powder changes from low to high.
