Yan Liye, Cinar Ahmet, Ma Shaocheng, Abel Richard, Hansen Ulrich, Marrow Thomas James
Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.
MSk Laboratory, Department of Surgery and Cancer, Faculty of Medicine, Imperial College, London, SW7 2AZ, UK.
J Mech Behav Biomed Mater. 2020 Sep;109:103838. doi: 10.1016/j.jmbbm.2020.103838. Epub 2020 May 1.
The fracture resistance of load-bearing trabecular bone is adversely affected by diseases such as osteoporosis. However, there are few published measurements of trabecular bone fracture toughness due to the difficulty of conducting reliable tests in small specimens of this highly porous material. A new approach is demonstrated that uses digital volume correlation of X-ray computed tomographs to measure 3D displacement fields in which the crack shape and size can be objectively identified using a phase congruency analysis. The criteria for crack propagation, i.e. fracture toughness, can then be derived by finite element simulation, with knowledge of the elastic properties.
诸如骨质疏松症等疾病会对承重小梁骨的抗骨折能力产生不利影响。然而，由于在这种高度多孔材料的小样本中进行可靠测试存在困难，已发表的小梁骨断裂韧性测量数据很少。本文展示了一种新方法，该方法利用X射线计算机断层扫描的数字体积相关技术来测量三维位移场，在该位移场中，可以使用相位一致性分析客观地识别裂纹的形状和尺寸。然后，在了解弹性特性的情况下，通过有限元模拟可以得出裂纹扩展的标准，即断裂韧性。
