Abstract The effect of low temperature on the properties of moisture-saturated glass-fiber-reinforced plastic KAST-B was investigated by studying acoustic emission. During cooling of dried and moisture-saturated specimens with surface defects, the rms acoustic emission and the acoustic emission count rate remain within the background noise. It was determined for the first time that, if water is localized in a crack in the glass-fiber-reinforced plastic, then its cooling leads to an intense acoustic emission. It was assumed that this emission is caused by local damages of the polymer matrix because of the increase in the internal stresses as water turns to ice.

中文翻译：

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饱和水分复合材料冷却过程中裂纹尖端的声发射

摘要 通过声发射研究，研究了低温对饱和水分玻璃纤维增​​强塑料KAST-B性能的影响。在冷却具有表面缺陷的干燥且水分饱和的样品期间，rms 声发射和声发射计数率保持在背景噪声范围内。首次确定，如果水存在于玻璃纤维增​​强塑料的裂缝中，则其冷却会导致强烈的声发射。假设这种发射是由聚合物基体的局部损坏引起的，因为随着水变成冰，内部应力增加。