Introduction
Friction bonding process is a joining operation of two or
more metal sheets by using heat and mechanical force to
soften and provide an adhesion between the metal sheets. This
joining process is done in a solid status, where the work
materials are heated to a certain temperature before being
pressed together by a mechanical force. The amount of heat
and force used in the process is strongly dependent on the
work materials to be bonded. The lack in controlling of
process parameters could lead to the incomplete bonding or
delamination of the jointed parts. The delamination or the
presence of a gap between the incomplete bonded sheets can
cause a significant failure once the part is under a mechanical
or thermal load. In the manufacturing point of view, the
appearance of incomplete jointed section is responsible for the
number of rejected works so does the manufacturing costs.