Abstract：
:This paper investigates the effects of moisture, anisotropy, stress state, and strain rate on the mechanical properties of the bighorn sheep (Ovis Canadensis) horn keratin. The horns consist of fibrous keratin tubules extending along the length of the horn and are contained within an amorphous keratin matrix. Samples were tested in the rehydrated (35wt% water) and ambient dry (10wt% water) conditions along the longitudinal and radial directions under tension and compression. Increased moisture content was found to increase ductility and decrease strength, as well as alter the stress state dependent nature of the material. The horn keratin demonstrates a significant strain rate dependence in both tension and compression, and also showed increased energy absorption in the hydrated condition at high strain rates when compared to quasi-static data, with increases of 114% in tension and 192% in compression. Compressive failure occurred by lamellar buckling in the longitudinal orientation followed by shear delamination. Tensile failure in the longitudinal orientation occurred by lamellar delamination combined with tubule pullout and fracture. The structure-property relationships quantified here for bighorn sheep horn keratin can be used to help validate finite element simulations of ram's impacting each other as well as being useful for other analysis regarding horn keratin on other animals. STATEMENT OF SIGNIFICANCE:The horn of the bighorn sheep is an anisotropic composite composed of keratin that is highly sensitive to moisture content. Keratin is also found in many other animals in the form of hooves, claws, beaks, and feathers. Only one previous study contains high rate experimental data, which was performed in the dry condition and only in compression. Considering the bighorn sheep horns' protective role in high speed impacts along with the moisture and strain rate sensitivity, more high strain rate data is needed to fully characterize and model the material. This study provides high strain rate results demonstrating the effects of moisture, anisotropy, and stress state. As a result, the comprehensive data allows modeling efforts to be greatly improved.
journal_name
Acta Biomaterjournal_title
Acta biomaterialiaauthors
Johnson KL,Trim MW,Francis DK,Whittington WR,Miller JA,Bennett CE,Horstemeyer MFdoi
10.1016/j.actbio.2016.10.033subject
Has Abstractpub_date
2017-01-15 00:00:00pages
300-308eissn
1742-7061issn
1878-7568pii
S1742-7061(16)30560-8journal_volume
48pub_type
杂志文章abstract：UNLABELLED:The irritation/discomfort associated with the use of contact lenses (CLs) is often related to the eyelid-lens friction. Although the use of such devices is widespread, the information about the influence of the lacrimal fluid biomolecules on the tribological behavior of the CLs hydrogels is scarce. In this w...
journal_title：Acta biomaterialia
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journal_title：Acta biomaterialia
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journal_title：Acta biomaterialia
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journal_title：Acta biomaterialia
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journal_title：Acta biomaterialia
pub_type： 杂志文章
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更新日期：2009-06-01 00:00:00
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journal_title：Acta biomaterialia
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journal_title：Acta biomaterialia
pub_type： 杂志文章
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更新日期：2010-06-01 00:00:00
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pub_type： 杂志文章
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journal_title：Acta biomaterialia
pub_type： 杂志文章
doi：10.1016/j.actbio.2017.11.058
更新日期：2018-02-01 00:00:00
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journal_title：Acta biomaterialia
pub_type： 杂志文章
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pub_type： 杂志文章
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更新日期：2010-06-01 00:00:00
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更新日期：2007-01-01 00:00:00
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journal_title：Acta biomaterialia
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更新日期：2013-08-01 00:00:00
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pub_type： 杂志文章
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journal_title：Acta biomaterialia
pub_type： 杂志文章,评审
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更新日期：2020-04-15 00:00:00
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journal_title：Acta biomaterialia
pub_type： 杂志文章
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更新日期：2018-01-01 00:00:00
