The objective of this study was to experimentally determine
the effects of storage time, storage temperature, adhesive dispensing
line temperature and shear rate on the rheological characteristics
of three uncured single-part epoxy adhesives at the preapplication
and application stages. These adhesives are used for
joining steel panels in structural automotive applications. The preapplication
and application conditions were selected to represent
the current practice in the automotive assembly line. A parallel
plate viscometer was used to conduct the experiments. Power-law
viscosity model and shear rate–temperature superposition were
used to correlate the viscosity data in order to understand how the
experimental variables affect the adhesive viscosity before curing.
Currently, the adhesive industry uses a single-point data to indicate
the adhesive viscosity and does not take into account any
process parameter variations that may occur in production
applications