Failure property distributions for conventional and highly crosslinked ultrahigh molecular weight polyethylenes.
Failure property distributions for conventional and highly crosslinked ultrahigh molecular weight polyethylenes.
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常规和高度交联超高分子量聚乙烯的失效性能分布。
DOI：
10.1002/jbm.b.30163
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Rimnac,CM
中科院分区：
文献类型：
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作者：
Kurtz,SM;Bergström,J;Rimnac,CM
为了对常规或高交联超高分子量聚乙烯（UHMWPE）材料进行随机（概率）失效预测，不仅必须定义失效标准，而且还必须指定失效强度的概率分布。本研究旨在分别基于正态和Weibull模型分布，评价描述UHMWPE失效特性的参数和非参数统计方法。由于材料的疲劳和断裂特性在历史上已经使用威布尔统计进行了很好的描述，因此预计非参数方法将提供比参数方法更好的失效分布拟合。从先前进行的60次拉伸试验中分析了失效时的极限真应力、真应变和极限链条拉伸数据。对121次小冲杆试验的极限荷载和极限位移进行了分析。结果发现，正态分布和威布尔模型提供了一个合理的描述的集中趋势的故障分布。正态和威布尔模型之间的主要差异可以在分布尾端的预测下限响应中发现。数据支持使用参数和非参数方法对下限失效预测进行括号化，以模拟UHMWPE的失效阈值。© 2005威利期刊有限公司生物医学材料研究杂志B部分：应用生物材料
To make stochastic (probabilistic) failure predictions of a conventional or highly crosslinked ultrahigh molecular weight polyethylene (UHMWPE) material, not only must a failure criterion be defined, but it is also necessary to specify a probability distribution of the failure strength. This study sought to evaluate both parametric and nonparametric statistical approaches to describing the failure properties of UHMWPE, based on the Normal and Weibull model distributions, respectively. Because fatigue and fracture properties of materials have historically been well described with the use of Weibull statistics, it was expected that a nonparametric approach would provide a better fit of the failure distributions than the parametric approach. The ultimate true stress, true strain, and ultimate chain stretch data at failure were analyzed from 60 tensile tests conducted previously. The ultimate load and ultimate displacement from 121 small punch tests conducted previously were also analyzed. It was found that both Normal and Weibull models provide a reasonable description of the central tendency of the failure distribution. The principal difference between the Normal and Weibull models can be appreciated in the predicted lower‐bound response at the tail end of the distribution. The data support the use of both parametric and nonparametric methods to bracket the lower‐bound failure prediction in order to simulate the failure threshold for UHMWPE. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater