Fatigue behavior and damage mechanism of aluminum foam sandwich with carbon-fiber face-sheets

Abstract

Aluminum foam sandwich (AFS) has been used in engineering field, where cyclic loading is in most of the applications. However, limited research has been done on the fatigue behavior of AFS. In the present study, fatigue performance of AFS made of aluminum foam core and carbon-fiber face-sheet was studied experimentally by a high frequency fatigue test machine and the damage mechanisms of the structure were studied by SEM. Results indicated that the fatigue life of AFS decreased with the increasing loading level. The S-N curve of AFS obeys three-parameter lognormal distribution in most of the cases. AFS was sensitive to cyclic loading level and the load capacity after cyclic loading improved significantly when the cyclic loading level was lower. The main life of AFS was its crack initiation stage. Three categories of damage mechanisms were observed. This study is of great significance to the design and application of AFS.