Experimental characterization of a fiber metal laminate for underwater applications

The use of fiber reinforced plastics in underwater and environmental aggressive applications is limited due to their scarce resistance to moisture absorption. In this work, we characterize the mechanical prop- erties of a fiber metal laminate, where an outermost steel layer is utilized as protection against contam- ination. In particular, we perform experiments on wearing resistance, static strength characterization, moisture absorption, low-velocity impact behavior, dynamic behavior, and dynamic thermal analysis. Experiments are conducted on specimens conditioned in hot water and findings are compared against results obtained with dry specimens that underwent the same thermal cycles, but without being in contact with water. Results show that the water absorption in unprotected specimens decreases all the mechanical properties of the laminate. Instead, the outer protective metal layer is found to be very effective against water absorption, whereby results on the conditioned protected specimens are in line with the ones obtained for the dry specimens. Further, the protective steel layer is found to remarkably increase the wearing resistance.