在小尺度上使用形状记忆和超弹性陶
Alan Lai1, Zehui Du, Chee Lip Gan
1Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
概括
研究人员通过创建微小的,微晶的结构来开发出强大的形状记忆陶. 这些先进的材料克服了脆性,为高性能执行器提供了众多超弹性循环.
科学领域:
- 材料科学 材料科学 材料科学
- 智能材料是一种智能材料.
- 陶工程 陶工程 陶工程
背景情况:
- 形状记忆材料利用马氏体相变换进行热变压转换.
- 易碎的马氏体材料,如陶,由于在低压力和有限的循环寿命下破裂,往往会失败.
研究的目的:
- 为了抑制易碎的马氏体陶的故障.
- 开发强大的形状记忆陶,能够承受高应变和众多超弹性循环.
主要方法:
- 在马石陶中制造微型,微晶结构的制造.
- 机械性能的表征,包括应变循环和故障分析.
主要成果:
- 橄晶体结构显著降低在马氏体转化过程中的内部不匹配应力.
- 开发的形状记忆陶表现出强大的性能,承受超过50个超弹性循环和超过7%的应变.
- 在工程陶结构中,由于裂而导致的故障被抑制.
结论:
- 微小的小晶体结构是克服马氏体陶脆性的关键.
- 这些坚固的形状记忆陶代表了执行器的新一类智能材料.
- 属性包括高能输出,缓冲和高温可操作性.
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