Some components of the plane are mostly made of the carbon fibre strengthened composite. When this kind of material gets low velocity impact, apparently, no damage can be observed. However, the internal damage to the composite occurs, and the displayed form is the interlaminate stripping and such defects as cracks, etc. On the interlaminate resin occur so that the rigidity and the strength if components are outstandingly decreased. In this article, the tests of the drop hammer impact on the composite and its three-point bending and the observation of the internal damage status of the laminated plate by means of acoustic microscopy device are discussed. What is more, the shape of the impacting object is comprehensively studied. The conclusion is drawn as follows:
The maximum bending stress is reduced owing to the impact damage. The maximum bending stress does not change with the height of drop under the condition of the smaller diameter of a drop hammer while the maximum bending stress is reduced with the increase of the height of drop under the condition of the larger diameter of a drop hammer.
The bending modulus of elasticity is reduced owing to the impact damage. After completion of the test of the impact and the one of the three-point bending, the forms of the occurrence of stripping face are different. The stripping occurs on the interface between the interlaminate and the resin as a result of the former test while a lot of resin of which the majority plays the role of destruction is adhered around the fibre as a result of the latter.
Publication Source: Trends in NDE Science & Technology; Proceedings of the 14th World Conference on Non-Destructive Testing, New Delhi, 8-13 December 1996.Vol. 2, pages 691 - 694 Publisher:Ashgate Publishing Company
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