Lopez Maria I, Meza Martinez Pedro E, Meyers Marc A
Materials Science and Engineering Program, University of California, San Diego, La Jolla, USA.
Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, USA.
Acta Biomater. 2014 May;10(5):2056-64. doi: 10.1016/j.actbio.2013.12.016. Epub 2013 Dec 15.
The contributions of mesolayers, organic interlamellar layers and nanoasperities/mineral bridges to the strength of nacre from red abalone (Haliotis rufescens) shell nacre are investigated. Samples were demineralized and deproteinized to separate the organic and mineral components, respectively. Tensile tests were performed on both the isolated organic constituent and the isolated mineral. The strength of the isolated organic component suggests that growth bands play an important role in the mechanical behavior as they are thick regions of protein that are a significant fraction (∼0.4) of the total organic content. The thickness variation of the nacre tablets was measured and found to be a small fraction of the mean tablet thickness (0.568μm); the standard deviation is 26nm, indicating that the wedge mechanism of toughening does not operate in the nacre investigated. Results obtained from the isolated mineral validate the importance of the organic constituent as the mechanical properties decline greatly when the organic component is removed. The results presented herein add to the understanding of the mechanical response of the organic interlayers and growth bands and their effect on the toughness of the abalone nacre.
研究了中层、有机层间层和纳米粗糙/矿物桥对红鲍（Haliotis rufescens）贝壳珍珠层强度的贡献。分别对样品进行脱矿质和脱蛋白处理，以分离有机成分和矿物成分。对分离出的有机成分和分离出的矿物都进行了拉伸试验。分离出的有机成分的强度表明，生长带在力学行为中起重要作用，因为它们是蛋白质的厚区域，占总有机含量的很大一部分（约0.4）。测量了珍珠层片的厚度变化，发现其是平均片厚度（0.568μm）的一小部分；标准偏差为26nm，表明在所研究的珍珠层中增韧的楔形机制不起作用。从分离出的矿物获得的结果证实了有机成分的重要性，因为当去除有机成分时，力学性能会大大下降。本文给出的结果有助于理解有机层间层和生长带的力学响应及其对鲍鱼珍珠层韧性的影响。
