Superelasticity and Tunable Thermal Expansion across a Wide Temperature Range
来源期刊：JOURNAL OF MATERIALS SCIENCE TECHNOLOG2016年第8期
论文作者：Y.L.Hao H.L.Wang T.Li J.M.Cairney A.V.Ceguerra Y.D.Wang Y.Wang D.Wang E.G.Obbard S.J.Li R.Yang
文章页码：705 - 709
摘 要：Materials that undergo a reversible change of crystal structure through martensitic transformation（MT）possess unusual functionalities including shape memory, superelasticity, and low/negative thermal expansion. These properties have many advanced applications, such as actuators, sensors, and energy conversion, but are limited typically in a narrow temperature range of tens of Kelvin. Here we report that, by creating a nano-scale concentration modulation via phase separation, the MT can be rendered continuous by an in-situ elastic confinement mechanism. Through a model titanium alloy, we demonstrate that the elastically confined continuous MT has unprecedented properties, such as superelasticity from below 4.2 K to 500 K, fully tunable and stable thermal expansion, from positive, through zero, to negative, from below 4.2 K to 573 K, and high strength-to-modulus ratio across a wide temperature range.The elastic tuning on the MT, together with a significant extension of the crystal stability limit, provides new opportunities to explore advanced materials.
Y.L.Hao1，H.L.Wang1，T.Li2,3，J.M.Cairney2,3，A.V.Ceguerra2,3，Y.D.Wang4，Y.Wang5,6，D.Wang5，E.G.Obbard7，S.J.Li1，R.Yang1
1. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences2. School of Aerospace, Mechanical & Mechatronic Engineering, University of Sydney3. Australian Centre for Microscopy and Microanalysis, University of Sydney4. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing5. State Key Laboratory for Mechanical Behavior of Materials and Frontier Institute of Science and Technology, Xi’an Jiaotong University6. Department of Materials Science and Engineering, Ohio State University7. Department of Electrical Engineering and Telecommunications, University of New South Wales
摘 要：Materials that undergo a reversible change of crystal structure through martensitic transformation（MT）possess unusual functionalities including shape memory, superelasticity, and low/negative thermal expansion. These properties have many advanced applications, such as actuators, sensors, and energy conversion, but are limited typically in a narrow temperature range of tens of Kelvin. Here we report that, by creating a nano-scale concentration modulation via phase separation, the MT can be rendered continuous by an in-situ elastic confinement mechanism. Through a model titanium alloy, we demonstrate that the elastically confined continuous MT has unprecedented properties, such as superelasticity from below 4.2 K to 500 K, fully tunable and stable thermal expansion, from positive, through zero, to negative, from below 4.2 K to 573 K, and high strength-to-modulus ratio across a wide temperature range.The elastic tuning on the MT, together with a significant extension of the crystal stability limit, provides new opportunities to explore advanced materials.
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