Bone features a hierarchical architecture, as a result of which antagonistic properties like toughness and strength are achieved. On the macroscale, bone exhibits a distinct anisotropy and loading mode dependence, with a considerably lower strength in tension compared to compression. To better understand the mechanisms leading to this behavior, anisotropic tensile yield and failure properties of ovine bone were characterized on the length scale of a single lamella (3-7 μm) and then compared to compression data for the same scale [1]. In situ microtensile experiments were carried out using an improved testing methodology, developed to overcome typical issues encountered during small scale testing related to sample fabrication, sample handling and misalignment [2]. The methodology is based on self-aligning silicon grippers prepared by means of reactive ion etching and an optimized microtensile sample geometry that can be fabricated via focused ion beam (FIB) milling. The measured elastic modulus, strength, yield stress and strain at maximum stress are summarized in table 1.
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