Facesheet delamination of composite sandwich materials at cryogenic temperatures

A new, novel test method, associated analysis, and experimental procedures are developed to investigate the toughness of the facesheet-to-core interface of a sandwich material at cryogenic temperatures. The test method is designed to simulate the failure mode associated with facesheet debonding due to high levels of gas pressure in the honeycomb core. The effects of specimen orientation are considered, and the results of toughness measurements are presented. Comparisons are made between room and cryogenic test temperatures. It was determined that the test method is insensitive to specimen facesheet orientation and strain energy release rate increases with a decrease in the test temperature. A reasonable agreement between test and simulation was achieved at both temperatures.