Xian Chen
Hong Kong University of Science and Technology
Differential interference contrast microscopyOpticsLattice (order)Energy transformationComposite materialPyroelectricityMartensiteMaterials scienceDiffractionSynchrotronCondensed matter physicsAlloyOptoelectronicsShape-memory alloyX-ray crystallographyEngineering physicsDiffusionless transformationCrystallographyMicrostructureCompatibility (mechanics)Austenite
38Publications
10H-index
721Citations
Publications 34
Newest
#3Xian Chen (HKUST: Hong Kong University of Science and Technology)H-Index: 10
Abstract null null Buckling of rigid thin films on elastomer substrates underlies the fabrication foundation of stretchable soft electronics. Here we demonstrate an optical approach to in situ characterize the buckling of silicon microribbon driven by releasing the pre-stretched poly-dimethylsiloxane (PDMS) substrate at a controllable strain rate. The method, based on quantitative differential interference microscopy, directly captures the space–time evolution of the surface topography at a fram...
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#1Chenbo Zhang (HKUST: Hong Kong University of Science and Technology)H-Index: 3
#2Zeyuan Zhu (HKUST: Hong Kong University of Science and Technology)H-Index: 1
Last. Xian Chen (HKUST: Hong Kong University of Science and Technology)H-Index: 10
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The pyroelectricity of polar materials provides great potential for electricity generation from waste heat. The pyroelectric effect of the material can be magnificently enhanced at a first-order phase transformation due to the abrupt jump in spontaneous polarization within a narrow temperature range. Here, we show that the performance of energy conversion by phase transformation is inversely resonant with the hysteresis of thermally driven structural transformations in a (Ba1−xSrx) (Hf0.02Ce0.00...
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We propose a scheme for assigning the martensite variant using electron backscatter diffraction in a martensite material that undergoes a solid-solid phase transformation. Based on the solutions of the crystallographic equations of martensite, we provide an algorithm to assign martensite variants to a particular microscopic region, and to check the elastic compatibility of the microstructure corresponding to low hysteresis and high reversibility in shape memory alloys. This article is part of th...
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#1Chenbo ZhangH-Index: 3
#2Zhuohui ZengH-Index: 2
Last. Xian ChenH-Index: 10
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Searching for performant multiferroic materials attracts general research interests in energy science as they have been increasingly exploited as the conversion media among thermal, electric, magnetic and mechanical energies by using their temperature-dependent ferroic properties. Here we report a material development strategy that guides us to discover a reversible phase-transforming ferroelectric material exhibiting enduring energy harvesting from small temperature differences. The material sa...
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#1Chenbo ZhangH-Index: 3
#2Zhuohui ZengH-Index: 2
Last. Xian ChenH-Index: 10
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Searching for performant pyroelectric materials is gathering research interest for its potential in clean electricity generation and waste heat harvesting. Here we report achieving the giant pyroelectric effect in materials undergoing a first-order phase transformation with high reversibility by tuning the crystallographic compatibility. The single crystalline Ba0.95Ca0.05Ti0.99Zr0.005Ce0.005O3 shows a pyroelectric coefficient of 1.93 uC/(cm2K), substantially higher than that of most of the stat...
#1Chenbo Zhang (HKUST: Hong Kong University of Science and Technology)H-Index: 3
#2Zhuohui Zeng (HKUST: Hong Kong University of Science and Technology)H-Index: 2
Last. Xian Chen (HKUST: Hong Kong University of Science and Technology)H-Index: 10
view all 5 authors...
Pyroelectric energy converters are functional capacitors that use a pyroelectric material as the dielectric layer. By utilizing a first-order phase transformation of the material, a pyroelectric device can generate an adequate amount of electricity from small temperature fluctuations. However, most pyroelectric capacitors leak during energy conversion. In this paper, we analyze the thermodynamics of pyroelectric energy conversion with consideration of electric leakage. Our thermodynamic model is...
3 CitationsSource
#1Zhuohui Zeng (HKUST: Hong Kong University of Science and Technology)H-Index: 2
#2Hoi Chun Chiu (HKUST: Hong Kong University of Science and Technology)H-Index: 2
Last. Xian Chen (HKUST: Hong Kong University of Science and Technology)H-Index: 10
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Abstract We propose a new experimental mechanics method: dual beam-shear differential interference microscopy (DInM) for full-field surface deformation measurement. The method integrates the principles of differential interference contrast, photoelasticity, digital image correlation and the theories of continuum mechanics for a 4D quantification of the surface topography. Our first DInM prototype provides the lateral resolution of 787nm for up to 12% measurable out-of-plane strains. The resoluti...
3 CitationsSource
#1Mostafa Karami (HKUST: Hong Kong University of Science and Technology)H-Index: 7
#2Zeyuan Zhu (HKUST: Hong Kong University of Science and Technology)H-Index: 1
Last. Xian Chen (HKUST: Hong Kong University of Science and Technology)H-Index: 10
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Both crystallographic compatibility and grain engineering are super critical to the functionality of shape memory alloys, especially at micro- and nanoscales. Here, we report a bicrystal CuAl24Mn9 ...
2 CitationsSource
#1Yangang Liang (UMD: University of Maryland, College Park)H-Index: 5
#2Seung Hun Lee (UMD: University of Maryland, College Park)H-Index: 21
Last. Ichiro Takeuchi (UMD: University of Maryland, College Park)H-Index: 63
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Structural phase transitions serve as the basis for many functional applications including shape memory alloys (SMAs), switches based on metal-insulator transitions (MITs), etc. In such materials, lattice incompatibility between transformed and parent phases often results in a thermal hysteresis, which is intimately tied to degradation of reversibility of the transformation. The non-linear theory of martensite suggests that the hysteresis of a martensitic phase transformation is solely determine...
10 CitationsSource
#1Mostafa Karami (HKUST: Hong Kong University of Science and Technology)H-Index: 7
#2Nobumichi Tamura (LBNL: Lawrence Berkeley National Laboratory)H-Index: 56
Last. Xian Chen (HKUST: Hong Kong University of Science and Technology)H-Index: 10
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A mathematical description of crystal structure is proposed consisting of two parts: the underlying translational periodicity and the distinct atomic positions up to the symmetry operations in the unit cell, consistent with the International Tables for Crystallography. By the Cauchy-Born hypothesis, such a description can be integrated with the theory of continuum mechanics to calculate a derived crystal structure produced by solid-solid phase transformation. In addition, the expressions for the...
2 CitationsSource