Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Laser ablation assisted adhesive bonding of automotive structural composites

Conference ·
OSTI ID:6675

Laser ablation has been evaluated as a surface pretreatment prior to adhesive bonding. In prior experimental work, it was observed that when adhesively bonded, composite, single lap shear samples fail, the fracture often occurs at either the adhesive/adherend interface or in the resin rich surface layer of the composite. These two areas represent the weakest portion of the joint. Laser ablation pretreatment generates areas where the resin on the composite surface is selectively removed leaving behind exposed reinforcing fibers which are the major load bearing members of the composite. In a subsequent adhesive bonding operation, this allows portions of the fibers to be encapsulated in the adhesive while other portions of the fiber remain in the composite resin. This type of pretreatment permits fibers to bridge and reinforce the interface between adhesive and adherend. A secondary benefit is the removal of surface contaminantes by pyrolysis. Microscopic observation of laser ablated surfaces indicates a prominent, fiber rich area. Results of the mechanical evaluation indicated that the lap shear strength for laser ablated samples was significantly higher than specimens with no pretreatment or with solvent cleaning only, but were slightly lower than specimens that were mechanically roughened and cleaned with solvents prior to bonding.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN
Sponsoring Organization:
USDOE Office of Energy Research (ER)
DOE Contract Number:
AC05-96OR22464
OSTI ID:
6675
Report Number(s):
ORNL/CP-102637; EE 04 01 00 0; ON: DE00006675
Country of Publication:
United States
Language:
English