Author : Alireza Daneshmehr, Alireza Asa and Saeid Abazary

Delamination and Fracture are the most common failure mode in composite materials, since they will result in the reduction of stiffness and can grow throughout other layers. Buckling is consisted of two main stages including delamination and fracture. The complex failure mechanisms that are commonly considered as the distinctive characteristic of composites are being amenable to nondestructive test advance. This research adopts the acoustic emission technique to study the failure mechanisms and damage evolution of glass/polyester composite laminatesunder buckling loading has been carried out. The tested of glass/polyester composite specimens include two lay-up patterns: [450/-450]6s and [00]6s.Each specimen includes 12 layers whit ruck in surface , and the thickness of each layer is about 0.416 mm. Moreover,the microscopic properties of different composite specimens after fracture are watched and analyzed by scanning electron microscope (SEM).Based on the SEM conception, the controlling microscopic failure mechanisms of composites including the splitting matrix cracking, fiber/matrix interface debonding, fiber pull-out and breakage as well as delamination are identified.

Keywords: Acoustic Emission, Buckling, Failure Mechanisms.

Article published in International Journal of Current  Engineering  and Technology, Vol.2,No.4 (Dec- 2012)