Analysis of damage mechanics of unidirectional composites beams with acoustic emission method

Abstract

Attempts of evaluation of a composite material strength during any period of its use, with use of acoustic emission method (AE) were taken by many authors. In this paper author also tried to define the parameters of acoustic emission signal, which could univocally define the mechanism of a composite destruction at a given stage of its use.
It seemed that the agreed energy „MARSE” could have been treated as that parameter, but the tests and analysis of the obtained results did not enable to give a univocal evaluation. From the tests were obtained the separate signals coming from resin cracking and the signals created during failure of the fibres. The characteristic of frequency v=C/D, where C is the number of counts and D is the signal duration time, was introduced as the basis parameter, which enables to separate the signals. The analysis of the results enables to determine, univocally, the process of composite failure.