Elastic strains in antler trabecular bone determined by synchrotron X-ray diffraction
Elastic strains in antler trabecular bone determined by synchrotron X-ray diffraction
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DOI：
10.1016/j.actbio.2008.05.008
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发表时间：
2008-11-01
影响因子：
9.7
通讯作者：
Mummery, P. M.
中科院分区：
文献类型：
--
作者：
Akhtar, R.;Daymond, M. R.;Mummery, P. M.
鹿角小梁骨的微观结构和相关力学性能已经使用各种技术进行了研究。利用纳米压痕和x射线显微断层扫描分别表征了局部小梁的性质和三维结构。据报道，干燥骨的弹性模量为10.9 +/- 1.1 GPa，而完全水化骨的弹性模量为5.4 +/- 0.9 GPa。骨小梁的厚度和分离程度与牛骨小梁相当。x射线微层析成像进行的原位单轴压缩显示，由于其矿物质含量低，鹿角可能发生显著的结构重排，以小梁弯曲和屈曲为主。利用高能同步x射线衍射测量了小梁磷灰石晶体在原位单轴压缩下的弹性应变。在弹性加载过程中，应变主要由平行于加载方向的小梁来调节。在宏观屈服点之前，随着小梁的弯曲变形，内部应变增加，载荷也被重新分配到与加载方向不平行的小梁上。小梁壁的显著弯曲导致沿加载方向排列的小梁内出现拉伸应变。(C) 2008材料学报Elsevier Ltd.出版。版权所有。
The microstructure and associated mechanical properties of antler trabecular bone have been studied using a variety of techniques. The local trabeculae properties, as well as the three-dimensional architecture were characterized using nanoindentation and X-ray microtomography, respectively. An elastic modulus of 10.9 +/- 1.1 GPa is reported for dry bone, compared with 5.4 +/- 0.9 GPa for fully hydrated bone. Trabeculae thickness and separation were found to be comparable to those of bovine trabecular bone. Uniaxial compression conducted in situ during X-ray microtomography showed that antler can undergo significant architectural rearrangement, dominated by trabeculae bending and buckling, due to its low mineral content. High-energy synchrotron X-ray diffraction was used to measure elastic strains in the apatite crystals of the trabeculae, also under in situ uniaxial compression. During elastic loading, strain was found to be accommodated largely by trabeculae aligned parallel to the loading direction. Prior to the macroscopic yield point, internal strains increased as trabeculae deformed by bending, and load was also found to be redistributed to trabeculae aligned non-parallel to the loading direction. Significant bending of trabecular walls resulted in tensile strains developing in trabeculae aligned along the loading direction. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.