中文摘要：

贝壳珍珠层是软体动物壳的最内层，经过若干世纪的自然进化，贝壳珍珠层形成了优良的微结构，并使贝壳具有了相当高的强度、刚度及断裂韧性。本文利用扫描电镜（SEM）观察了鲍鱼贝壳珍珠层的主要微结构特征，发现其是由层状的无机文石片和有机胶原蛋白质组成的生物陶瓷复合材料。根据发现的贝壳珍珠层层状微结构特征，建立贝壳珍珠层三维有限元模型，并用此模型分析了珍珠层的拉伸屈服极限与无机文石片拉伸屈服极限及其厚度的关系，研究表明珍珠层的屈服极限随无机文石片屈服极限的增加和无机文石片厚度的减小而增加。

英文摘要：

Nacre is the inner layer of mollusc shell. Nacre possesses excellent microstructure which is refined over many centuries and endows the shell with high strength, stiffness and fracture toughness. In the paper, the main microstructure of an abalone shell was observed with a scanning electron microscope （SEM）. It was found that the shell is a bio-ceramic composite consisted of layered inorganic aragonite sheets and organic collagen. Based on the observed microstructure a three-dimensional element finite model of the nacre is built. The mechanical property of the nacre, which is related to the property and the thickness of the aragonite sheets, are analyzed based on the model. The analysis results show that the yield limit of the nacre increases with the increase of the yield limit of the aragonite sheets and the decrease of the thickness of the aragonite sheets.