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Staggered Quadrupolar Phase and Bicritical Point of Spin-1 Bond and anisotropy Dilution Blume-Emery-Griffiths Model

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Communications in Theoretical Physics 2008年第2期49卷 511-515页

作者： DONG Heng-Ping YAN Shi-Lei Department of Physics Suzhou University Suzhou 215006 China Jiangsu key Loboratory of Thin Films Suzhou University Suzhou 215006 China Department of Physics Nanjing University Nanjing 210093 China CCAST （World Loboratory） P.O. Box 8730 Beijing 100080 China

Within the effective field theory （EFT）, staggered quadrupolar phase and bicritical point of spin-1 bond and anisotropy dilution Blume-Emery-Griffiths model is studied on simple cubic lattice in the restricted range of biquadratic interaction and bilinear interaction ratio α≤-1. The phase diagrams present a line of staggered quadrupolarparamagnetic （SQ-P） phase and a line of ferromagnetic-paramagnetic （F-P） phase, separated by a bicritical point （BCP）. A large negative ratio and two different dilution factors magnify the range of the SQ phase and reduce range of ferro- magnetic phase in T-α or T-D plane. These parameters can assist the reentrant behavior of the SQ-P line and suppress that of the F-P line. The influence of bond dilution on the BCP is dissimilar to that of anisotropy dilution. There is a degenerate pattern at ground state in T-D plane. Some results obtained by the pure BEG model is in qualitative agreement with the results of Monte Carlo simulations.

关键词： Blume-Emery-Grifiiths model staggered quadrupolar phase bicritical point bond and anisotropy dilution

The effects of orientation control via tension-compression on microstructural evolution and mechanical behavior of AZ31 Mg alloy sheet

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Journal of Magnesium and Alloys 2022年第2期10卷 446-458页

作者： Qingshan Yang Bin Jiang Bo Song Zujian Yu Dewei He Yanfu Chai Jianyue Zhang Fusheng Pan School of Metallurgy and Material Engineering Chongqing University of Science and TechnologyChongqing 401331China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of materials and Energy Southwest UniversityChongqing400715China MagIC–Magnesium Innovation Centre Helmholtz-Zentrum GeesthachtMax-Planck-Straße 1Geesthacht 21502Germany School of Engineering Technology Purdue UniversityWest LafayetteIN 47907-2021United States

The grain orientation control via twinning activity on deformation features is of great significance to offer a key insight into understanding the deformation mechanism of Mg alloy ***{10–12}twinning were performed by pre-strain paths,i.e.,tension(6%)and compression(5%)perpendicular to the c-axis along extrusion direction(ED),to investigate the microstructural evolution and mechanical properties of AZ31 Mg alloy *** distinction in the texture evolution and strain hardening behavior was illustrated in connection with the pre-strain paths for the activities of twinning and *** result shows that the activation of the deformation mode was closely bound up with the grain orientation and the additional applied load ***{10–12}twin-texture components with c-axis//ED were generated by precompression,which can provide an appropriate alternative to accommodate the thin sheet thickness strain and enhance the room temperature formability of Mg alloy sheet.

关键词： Mg alloy Orientation control Microstructural evolution texture Stretch formability

Mechanical Property Evaluation of a SLMed Martensitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1466-1476页

作者： Yun Shi Xiaojing Xiong Zhengwu Liu Yi Yang Juan Hou Songquan Wu Jeremy H.Rao Kai Zhang Aijun Huang Shanghai Aerospace Equipments Manufacturer Co. LtdShanghai 200245China Shanghai Research Center of Complex Metal Parts by Additive Manufacturing Shanghai 200245China Monash(Suzhou)Engineering Technology Co. LtdSuzhou 215123China School of materials Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China Future Industries Institute University of South AustraliaMawson LakesSA 5095Australia Monash Centre for Additive Manufacturing(MCAM) Monash UniversityClaytonVIC 3800Australia

A martensitic stainless steel AISI420 fabricated by selective laser melting(SLM)and post-processed by austenitizing and tempering heat treatment was investigated in this *** as-fabricated SLMed AISI420 showed a strong mechanical property anisotropy and low ductility in the longitudinal *** microstructural characterization revealed the presence of austenite and a relatively sharp solidification texture in the as-fabricated state,while the sharp texture was considered as the cause for the mechanical property *** contrast,a fully martensitic microstructure with a very weak texture was achieved after the austenitizing and tempering heat *** mechanical property anisotropy was also fully eliminated,witnessing a significant improvement in the ductility,and thus,comparable mechanical performance with the wrought product was achieved in this study.

关键词： Selective laser melting Microstructures Tensile testing Electron backscattered diff raction(EBSD) Martensitic steel

Remote Sensing Image Classification Algorithm Based on texture Feature and Extreme Learning Machine

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Computers, materials & Continua 2020年第11期65卷 1385-1395页

作者： Xiangchun Liu Jing Yu Wei Song Xinping Zhang Lizhi Zhao Antai Wang Media Computing laboratory School of Information EngineeringMinzu University of ChinaBeijing100081China School of Telecommunication Engineering Beijing PolytechnicBeijing100176China National Language Resource Monitoring and Research Center of Minority Languages Minzu University of ChinaBeijing100081China New Jersey Institute of Technology NewarkNJ 07102USA

With the development of satellite technology,the satellite imagery of the earth’s surface and the whole surface makes it possible to survey surface resources and master the dynamic changes of the earth with high efficiency and low *** an important tool for satellite remote sensing image processing,remote sensing image classification has become a hot *** to the natural texture characteristics of remote sensing images,this paper combines different texture features with the Extreme Learning Machine,and proposes a new remote sensing image classification *** experimental tests are carried out through the standard test dataset SAT-4 and *** results show that the proposed method is a simpler and more efficient remote sensing image classification *** also achieves 99.434%recognition accuracy on SAT-4,which is 1.5%higher than the 97.95%accuracy achieved by *** the same time,the recognition accuracy of SAT-6 reaches 99.5728%,which is 5.6%higher than DeepSat’s 93.9%.

关键词： Image classification gray level co-occurrence matrix extreme learning machine

预氧化对Co-Al-W基高温合金高温氧化和热腐蚀行为的影响

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金属学报 2019年第10期55卷 1273-1281页

作者：高博王磊宋秀刘杨杨舒宇千叶晶彦东北大学材料各向异性与织构教育部重点实验室沈阳110819 东北大学材料科学与工程学院沈阳110819 沈阳大学机械工程学院沈阳110044 Institute for materials Research Tohoku University Sendai 980-8577 Japan

将900℃常氧分压(900-PreO)、950℃常氧分压(950-PreO)和1000℃低氧分压(1000-LPreO)预氧化应用于Co-Al-W基高温合金,研究其高温氧化和热腐蚀行为,利用XRD、SEM和EDS表征了合金氧化层的结构和形貌特征。结果表明,采用900-PreO、950-PreO... 详细信息

将900℃常氧分压(900-PreO)、950℃常氧分压(950-PreO)和1000℃低氧分压(1000-LPreO)预氧化应用于Co-Al-W基高温合金,研究其高温氧化和热腐蚀行为,利用XRD、SEM和EDS表征了合金氧化层的结构和形貌特征。结果表明,采用900-PreO、950-PreO和1000-LpreO均可获得结构致密的预氧化层。1000℃氧化时,900-PreO预氧化层中的Cr2O3层进一步氧化而减薄,削弱了其对O及金属元素扩散的阻碍,致使氧化增重与未预氧化合金的情况相近;1000-LPreO预氧化生成的TiTaO4层易开裂,导致氧化层脱落严重,抗氧化性能较差;而950-PreO预氧化生成的CoCr2O4和Al2O3层致密且连续,氧化层的保护性强,氧化增重减缓。Co-Al-W基高温合金的热腐蚀中,950-PreO预氧化层中的CoWO4和Al2O3层阻止腐蚀介质进入合金基体,腐蚀增重锐减超过了80%。

关键词： Co-Al-W基高温合金预氧化高温氧化热腐蚀氧化层

Ultra-broadband reflectionless Brewster absorber protected by reciprocity

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Light(Science & Applications) 2021年第5期10卷 931-940页

作者： Jie Luo Hongchen Chu Ruwen Peng Mu Wang Jensen Li Yun Lai School of Physical Science and Technology Soochow UniversitySuzhou215006China National laboratory of Solid State Microstructures School of Physicsand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing210093China Department of Physics The Hong Kong University of Science and TechnologyClear Water BayHong KongChina William Mong Institute of Nano Science and Technology The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

The Brewster’s law predicts zero reflection of p-polarization on a dielectric surface at a particular ***,when loss is introduced into the permittivity of the dielectric,the Brewster condition breaks down and reflection unavoidably *** this work,we found an exception to this long-standing dilemma by creating a class of nonmagnetic anisotropic metamaterials,where anomalous Brewster effects with independently tunable absorption and refraction *** loss-independent Brewster effect is bestowed by the extra degrees of freedoms introduced by anisotropy and strictly protected by the reciprocity *** bandwidth can cover an extremely wide spectrum from dc to optical *** examples of reflectionless Brewster absorbers with different Brewster angles are both demonstrated to achieve large absorbance in a wide spectrum via microwave *** work extends the scope of Brewster effect to the horizon of nonmagnetic absorptive materials,which promises an unprecedented wide bandwidth for reflectionless absorption with high efficiency.

关键词： polarization absorber dielectric