Abstract
The acoustic emission responses (AE) of the multi-layered hybrid composite made of many thin aluminum sheets and CFRP sheets were studied under three conditions of uniaxial tensile, unloading -reloading and loading-holding tests. The failure processes were monitored and identified by the AE. The mechanisms of hybrid effect which had been found in the previous paper were clarified on the basis of AE data obtained under the condition of uniaxial tensile test. By analysing AE data obtained under each condition it was also found that there was a stress range in which a few cracks were generated in the matrix but did not propagate. This fact made it possible to decide an allowable stress for the tested material by the AE technique. As the stress in the specimen increased more than the allowable stress during loading-holding testing, a large amount of AE events were generated suddenly. It was thought that they resulted from delaminating of aluminum and CFRP laminae and that the failure mechanism controlling the uniaxial tensile testing changed into the other one which includes a delamination mechanism.
