Microstructural and mechanical challenges in biomedical NiTi
Microstructural and mechanical challenges in biomedical NiTi
复制标题
生物医学镍钛合金的微观结构和机械挑战
DOI：
10.1088/1742-6596/240/1/012004
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
M.F.-X. Wagner
中科院分区：
文献类型：
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作者：
M.F.-X. Wagner
NiTi形状记忆合金的力学行为表面上类似于某些生物材料，如骨骼或组织：由于可逆的马氏体相变，NiTi合金可以恢复相对较大的应变；单轴应力-应变曲线表现出恒定的应力平台（在几百MPa，取决于合金成分和测试温度）与相变相关。这些新颖的功能特性，结合超细颗粒NiTi的高机械强度和良好的生物相容性，被用于各种植入物和医疗器械。然而，与分层结构的生物材料非常相似，NiTi的变形行为与几个长度尺度上不同的变形过程错综复杂地联系在一起，并且在我们对微观结构-性能关系的理解上仍然存在重大差距。在本文中，最近的实验和理论结果从第一性原理计算，微力学建模和纳米压痕进行了讨论，重点是非弹性变形过程的作用，孪晶界和塑性变形和应力诱导相变的相互作用。这些新发现挑战了我们对NiTi基本力学特性的理解。他们强调了非弹性变形机制对NiTi整体力学性能和强度的重要性。
The mechanical behaviour of NiTi shape memory alloys superficially resembles that of certain biomaterials, such as bones or tissues: By virtue of a reversible martensitic phase transformation, NiTi alloys can recover relatively large strains; uniaxial stress-strain curves exhibit constant stress-plateaus (at several hundreds of MPa, depending on alloy composition and testing temperature) associated with the phase transition. These novel functional properties, in combination with high mechanical strength in ultra-fine grained NiTi and good biocompatibility, are utilized in various implants and medical devices. Yet–and quite similar to hierarchically structured biomaterials–the deformation behaviour of NiTi is intricately linked to distinct deformation processes on several length scales, and there remain significant gaps in our understanding of the microstructure-property relations. In the present paper, recent experimental and theoretical results from first-principles calculations, micromechanical modelling and nanoindentation are discussed with a focus on the role of inelastic deformation processes, twin boundaries and the interaction of plastic deformation and stress-induced phase transformations. These novel findings challenge our understanding of the fundamental mechanical properties of NiTi. They highlight the importance of inelastic deformation mechanisms for the overall mechanical properties and strength of NiTi.
伪弹性 NiTi 传播界面处的应变映射
影响因子：
3.8
作者：
A. Schaefer;M. Wagner
通讯作者：
M. Wagner
用于微型伪弹性 NiTi 样品原位应变的透射电子显微镜程序
DOI：
--
发表时间：
2008
期刊：
影响因子：
--
作者：
J. Olbricht;M. Wagner;A. Condó;A. Dlouhý;C. Grossmann;A. Kröger;C. Somsen;G. Eggeler
通讯作者：
G. Eggeler
NiTi 纳米压痕过程中微观结构演变的 TEM 研究
DOI：
--
发表时间：
2009
期刊：
影响因子：
--
作者：
J. Pfetzing;M. Wagner;T. Simon;A. Schaefer;C. Somsen;G. Eggeler
通讯作者：
G. Eggeler