Shear-induced adhesive failure of a rigid slab
in contact with a thin confined film |
| |
Authors: | M K Chaudhury K H Kim |
| |
Institution: | (1) Department of Chemical Engineering, Lehigh University, Bethlehem, PA 18015, USA |
| |
Abstract: | A rigid-glass prism (square or rectangular base,
rectangular cross-section) is sheared off a thin film of silicone
elastomer bonded to a glass plate by applying a tangential force
at various distances above the prism/elastomer interface. At a
given tangential force, the prism starts to slide on the
elastomeric film. As the sliding velocity, thus the frictional
force, is progressively increased, an elastic instability
develops at the interface that results in the formation of
numerous bubbles. These bubbles, the lateral dimension of which
is comparable to the thickness of the film, move across the
interface with speeds 1000 times faster than the overall sliding
speed of the glass prism against the PDMS film. It is found that
the glass prism continues to slide on the elastomeric film as
long as the applied shear stress is less than a critical value.
During sliding, however, a normal stress is developed at the
interface that decays from the front (i.e. where the
force is applied) to the rear end of the prism. When the normal
stress reaches a critical value, the prism comes off the film. The
critical shear stress of fracture increases with the modulus of
the film, but decreases with the thickness following a square root
relationship, as is the case with the removal of rigid punches
from thin elastomeric films by normal pull-off forces. |
| |
Keywords: | 68 35 -p Solid surfaces and solid-solid interfaces: Structure and energetics 46 50 +a Fracture mechanics fatigue and cracks 68 35 Np Adhesion |
本文献已被 PubMed SpringerLink 等数据库收录! |
|