海水对PMI泡沫夹芯复合材料吸湿性能以及力学性能的影响

EFFECT OF SEAWATER ON HYGROSCOPICITY AND MECHANICAL PROPERTIES OF PMI FOAM SANDWICH COMPOSITES

随着泡沫夹芯复合材料在船舶领域的应用越来越广泛,海洋环境对泡沫夹芯复合材料性能的影响有待探究。本文通过对比去离子水和海水对PMI泡沫夹芯复合材料吸湿性能和力学性能的差异,探究海水对泡沫夹芯复合材料影响的机理。实验结果表明:PMI泡沫夹芯复合材料浸泡在海水中饱和吸湿率为5.4%,达到饱和所需时间为28d;而浸泡在去离子水中的样品的饱和吸水率以及达到饱和所需时间分别为6.9%、30d;通过Fick第二扩散定律发现海水中的水分子的扩散系数要低于去离子水中水分子的扩散系数。此外,浸泡在去离子水中样品的平压强度、侧压强度和弯曲强度分别降低了37.78%、16.72%、23.71%;而浸泡在海水中样品的性能分别下降了35.56%、21.2%、20.63%。

With the increasing use of foam sandwich composites in the marine industry, the impact of the marine environment on the performance of foam sandwich composites remains to be explored. In this paper, the mechanism of the influence of seawater on foam sandwich composites was investigated by comparing the difference in hygroscopicity and mechanical properties of PMI foam sandwich composites with deionized water and seawater. The test results show that the saturated moisture absorption rate of PMI foam sandwich composites immersed in seawater is 5.4%, and the time required for saturation is 28 days. The saturated water absorption rate and the time required for saturation of samples immersed in deionized water are 6.9% and 30 days, respectively. Through Fick′s second law of diffusion, the diffusion coefficient of water molecules in seawater is lower than that of water molecules in deionized water. In addition, the flat compressive strength, lateral compressive strength and flexural strength of the samples immersed in deionized water are decreased by 37.78%, 16.72%, and 23.71%, respectively, while the samples immersed in seawater are decreased by 35.56%, 21.2%, and 20.63%, respectively.