Durability of end-grain balsa core material in the marine environment

摘要

End-grain balsa core material has enjoyed wide usage in sandwich composite applications One may question the logic of using a wood product in the marine environment, where the potential for moisture ingress is not only real, but seemingly unavoidable. A spate of failed marine surveys of balsa-cored fiberglass pleasure boats started appearing in the year 2000. One manufacturer appealed to us to assist in not only rectifying their "wet-core" quandary, but also to identify the effect of moisture content on end-grain balsa's physical properties, assess the rate of moisture migration across exposed end-grain balsa core in a sandwich laminate at unprotected through-holes, and determine the potential for freeze-induced delaminations should the core and kerf network become saturated with water and freeze.