Ultrasonic and thermal testing as a diagnostic tool for the evaluation of cumulative discontinuities of the polyester – glass pipe structure

The wide spectrum of applications with reference to polymer composites causes that they are exposed to many degradation factors which have significant impact on their functional properties. These are both environmental factors (e.g temperature, microorganisms or UV radiation) [1, 2, 5, 6, 8, 10, 12] and fatigue ones (e.g. the value of tensions, frequency) [4, 18, 19]. Synergism of the phenomena triggered by these factors leads to gradual material degradation, which is particularly important in the case of polymer material [18, 22]. Properties of the polymer constructional composites, including glass-polyester ones depend, among others, on characteristics of input materials (reinforcements, matrixes), their mutual, adhesive connection and the technology of production. If wrongly matched, even one of the factors, causes the decrease in composite properties. Relatively large impact on the quality of obtained composites has the technology of their production [9, 11, 13]. It has been proved that in the winding technology [11] wrongly matched tension force causes bad fiber supersaturation, which in turn leads to appearance of flaws like voids or discontinuities. Małgorzata SzyMiczek