Study of polyurethane elastomer cores interfacial fracture resistance of the sandwich materials for ship structures

The use of sandwich materials continues to grow in several engineering applications. In line with this trend, the marine industry is also adopting steel-based sandwich materials with polyurethane elastomer cores as primary materials to substitute the steel ship structures. Using lightweight and thick core material gives added stiffness without significantly increasing the structure's weight. However, it poses a challenge when dealing with damage vulnerability due to the differences in faceplates and core material properties, especially at the interface of two layers. Therefore, the resistance to fracture is an important design parameter to be determined. This study approaches measuring the interfacial fracture resistance of the steel faceplate and polyurethane elastomer core. The interfacial fracture resistance is quantified as the Energy Release Rate (ERR) estimated due to mode-I and mode-II loading. The interfacial fracture resistance employs experimental and numerical methods, and the result under mode-I loading shows valid agreement. However, more accurate numerical methods are necessary to represent the experimental conditions for mode-II loading.