Department of Mechanical Engineering, Center for Advanced Vehicular Systems (CAVS), Mississippi State University, Mississippi State, MS 39762, USA.
Acta Biomater. 2011 Mar;7(3):1228-40. doi: 10.1016/j.actbio.2010.11.024. Epub 2010 Nov 21.
The function of the bighorn sheep horn prompted quantification of the various parametric effects important to the microstructure and mechanical property relationships of this horn. These parameters included analysis of the stress-state dependence with the horn keratin tested under tension and compression, the anisotropy of the material structure and mechanical behavior, the spatial location along the horn, and the wet-dry horn behavior. The mechanical properties of interest were the elastic moduli, yield strength, ultimate strength, failure strain and hardness. The results showed that water has a more significant effect on the mechanical behavior of ram horn more than the anisotropy, location along the horn and the type of loading state. All of these parametric effects showed that the horn microstructure and mechanical properties were similar to those of long-fiber composites. In the ambient dry condition (10 wt.% water), the longitudinal elastic modulus, yield strength and failure strain were measured to be 4.0 G Pa, 62 MPa and 4%, respectively, and the transverse elastic modulus, yield strength and failure strain were 2.9 GPa, 37 MPa and 2%, respectively. In the wet condition (35 wt.% water), horn behaves more like an isotropic material; the elastic modulus, yield strength and failure strain were determined to be 0.6G Pa, 10 MPa and 60%, respectively.
大角羊角的功能促使对各种参数效应进行量化，这些参数效应对这种角的微观结构和机械性能关系非常重要。这些参数包括在拉伸和压缩下测试角蛋白时的应力状态依赖性分析、材料结构和机械行为的各向异性、沿着角的空间位置以及干湿角的行为。感兴趣的力学性能包括弹性模量、屈服强度、极限强度、破坏应变和硬度。结果表明，水对角的力学行为的影响比各向异性、沿着角的位置和加载状态的类型更为显著。所有这些参数效应表明，角的微观结构和力学性能与长纤维复合材料相似。在环境干燥条件（10wt.%水）下，测量到的纵向弹性模量、屈服强度和破坏应变为 4.0GPa、62MPa 和 4%，横向弹性模量、屈服强度和破坏应变为 2.9GPa、37MPa 和 2%。在潮湿条件（35wt.%水）下，角表现得更像各向同性材料；确定的弹性模量、屈服强度和破坏应变为 0.6GPa、10MPa 和 60%。
