Unraveling Grit-Blasting Effects
This paper is part of an ongoing collaboration between Dr. Giles Dillingham, BTG Lab's chief scientist, and other members of the University of Cincinnati’s Department of Chemical and Material Engineering, Boeing, and the Materials Directorate of the Wright Patterson Air Force Base to study the effects of grit-blasting on graphite/epoxy composites.
Grit-blasting, a commonly used surface preparation process frequently applies to polymer composites. However, very little experiments and observations exist concerning the effects of grit-blasting on the surface properties of composites.
Increasing Surface Energy
This study examines the effects of 2 types of grit-blasting on the surface of graphite/epoxy composites. Using a Goniometer to determine surface energy, contact angles were measured before and after grit blasting with an 80- and 220-grit garnet and a 220-grit aluminum. While the 220-grit alumina produced the highest surface energy increase, calculable changes in surface chemistry, as well as changes in the surface morphology of the composites appeared. Furthermore, grit-blasting showed a similar increase in surface energy, comparable to plasma treatment. Not all composites responded the same, leaving leeway for error and inconsistencies in surface preparation using grit-blasting. This stresses the importance of surface energy monitoring to avoid these inconsistencies and possible errors.
Visit our Technical Resources page to read the full article on effectively measuring the effects of grit-blasting and it's comparison to other surface treatment methods.