Post Impact Compression Strength(PICS)Evaluation of Glass/Epoxy Composite Using a Novel Approach-Effect of Delamination Area

摘要

Woven glass fabric epoxy composite laminates were subjected to low velocity impacts in an uninstrumented drop weight tester,and the corresponding delamination areas traced.The compression strengths of the composite before and after the impact event were measured adopting a novel technique,consisting of tests on a scaled down version of the standard Boeing-CAI specimen,using a custom designed compression test fixture,in order to facilitate tests within the capacity of an available 100 kN testing machine.Experimental data showed that,as the incident impact energy(E_(in))was increased from 10J to 25 J,the delamination area(A_(del)increased from 369 mm2 to 640 mm~2,and the compression strength retained was in the range of 62.73% to 43.17% of its virgin strength.Further,a concept of"Area Retention Factor"has been introduced to explain the phenomenon causing the compression strength degradation(or its retention)in impact damaged composites.