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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.