  The present contribution focuses on the effect of adherend surface roughness
on the strength of adhesive joints, which are particularly cost-effective and
extensively applied in a wide range of industrial applications. However, the
reliability of such solutions is a critical concern for the integrity of
commercial products. To gain a deeper understanding on the effect of roughness,
an extensive experimental campaign is proposed, where thermoplastic substrates
are produced with a specified roughness, whose characterization has been
performed using a confocal profilometer. Elastic strips are then bonded onto
such substrates using Silicone adhesive while controlling the adhesive
thickness. Peeling tests are finally carried out and the effects of joint
parameters such as surface roughness, adhesive thickness, and loading rate are
discussed in detail. Eventually, it is demonstrated that the surface roughness
can increase the adhesion energy of joints depending on the value of a ratio
between the adhesive thickness and the root mean square elevation of roughness.
