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Acta Mechanica Solida Sinica 2021年第2期34卷 237-251页

作者： Li Zhang Junhong Guo yongming xing Department of Mechanics Inner Mongolia University of TechnologyHohhot 010051China School of Aeronautics Inner Mongolia University of TechnologyHohhot 010051China

In this study,the nonlocal strain gradient theory is adopted to investigate the static bending deformation of a functionally graded(FG)multilayered nanoplate made of onedimensional hexagonal piezoelectric quasicrystal(PQC)materials subjected to mechanical and electrical surface *** FG materials are assumed to be exponential distribution along the thickness *** closed-form solutions of an FG PQC nanoplate including nonlocality and strain gradient micro-size dependency are derived by utilizing the pseudo-Stroh *** propagator matrix method is further used to solve the multilayered case by assuming that the layer interfaces are perfectly *** examples for two FG sandwich nanoplates made of piezoelectric crystals and PQC are provided to show the influences of nonlocal parameter,strain gradient parameter,exponential factor,length-to-width ratio,loading form,and stacking sequence on the static deformation of two FG sandwich nanoplates,which play an important role in designing new smart composite structures in engineering.

关键词： Nonlocal strain gradient theory Functionally graded material.Quasicrystal.Multilayered nanoplates Propagator matrix method

Complex variable method for an anti-plane elliptical cavity of one-dimensional hexagonal piezoelectric quasicrystals

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Chinese Journal of Aeronautics 2015年第4期28卷 1287-1295页

作者： Yu Jing Guo Junhong xing yongming School of Science Inner Mongolia University of Technology College of General Education Inner Mongolia Normal University

Based on the fundamental equations of piezoelasticity of quasicrystal media, using the symmetry operations of point groups, the linear piezoelasticity behavior of one-dimensional（1D）hexagonal quasicrystals is investigated and the piezoelasticity problem of 1D hexagonal quasicrystals is decomposed into two uncoupled problems, i.e., the classical plane elasticity problem of conventional hexagonal crystals and the phonon–phason-electric coupling elasticity problem of1 D hexagonal *** final governing equations are derived for the phonon–phasonelectric coupling anti-plane elasticity of 1D hexagonal *** complex variable method for an anti-plane elliptical cavity in 1D hexagonal piezoelectric quasicrystals is proposed and the exact solutions of complex potential functions, the stresses and displacements of the phonon and the phason fields, the electric displacements and the electric potential are obtained *** the cavity into a crack, the explicit solutions in closed forms of electro–elastic fields,the field intensity factors and the energy release rate near the crack tip are derived.

关键词： Complex variable methodElliptical cavity Fracture mechanics Piezoelasticity Quasicrystals

Quantitative analysis of nanoscale deformation fields of a crack-tip in single-crystal silicon

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Science China(Physics,Mechanics & Astronomy) 2012年第6期55卷 1088-1092页

作者： ZHAO ChunWang xing yongming College of Science Inner Mongolia University of TechnologyHohhot 010051China

A mode II crack in single-crystal silicon was investigated experimentally using high-resolution transmission electron *** phase analysis and numerical moiré method were employed to map the deformation fields of the crack-tip *** normal strain field maps of the crack-tip area indeed showed the deformation occurs primarily in the vicinity of the dislocations and the normal strains are near zero in the crack-tip *** shear strain field map shows that the relatively large shear strain is in the crack-tip *** experimental results were compared with the predictions of linear elastic fracture *** comparison shows that measured strain distribution ahead of the crack-tip agrees with the predictions of linear elastic fracture mechanics up to 1 nm from the crack-tip.

关键词： crack-tip strain high-resolution transmission electron microscopy geometric phase analysis

Micromechanical characteristics of the asphalt mixture in bending condition

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Science China(Technological Sciences) 2013年第2期56卷 392-397页

作者： CUI YaNan xing yongming NI WenChen College of Civil Engineering Inner Mongolia University of Technology Colleges of Science Inner Mongolia University of Technology

The characteristics of asphalt mixtures are associated with the key features of the mixed material when it is not ***-dimensional(2D) microstructure images of asphalt mixture bending beam specimen were captured by a CCD *** image processing,such as noise elimination,boundary identification,image binarization and vectorization,the images were imported into finite element(FE) software in order to set up the micromechanical finite element(FE) *** simulation results show that the displacement contours spectrum is not a smooth curve since the mixed material is ***,the largest strain value exists at the bottom of the specimen between two coarse aggregates,and it is the point where the fracture *** stress values of aggregates are larger than those of the asphalt *** from the strain of asphalt matrix,the strain of aggregates is close to zero because the aggregates have higher capability to resist *** difference in deformation between aggregate and asphalt matrix can lead to an interface crack as a final *** these results can be improved by three-point bending test of asphalt mixture beam.

关键词： micromechanics composites asphalt mixtures finite-element method

General solutions of plane problem in one-dimensional quasicrystal piezoelectric materials and its application on fracture mechanics

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Applied Mathematics and Mechanics(English Edition) 2015年第6期36卷 793-814页

作者： Jing YU Junhong GUO Ernian PAN yongming xing School of Science Inner Mongolia University of Technology College of General Education Inner Mongolia Normal University Department of Civil Engineering University of Akron

Based on the fundamental equations of piezoelasticity of quasicrystals （QCs）, with the symmetry operations of point groups, the plane piezoelasticity theory of one- dimensional （1D） QCs with all point groups is investigated systematically. The gov- erning equations of the piezoelasticity problem for 1D QCs including monoclinic QCs, orthorhombic QCs, tetragonal QCs, and hexagonal QCs are deduced rigorously. The general solutions of the piezoelasticity problem for these QCs are derived by the opera- tor method and the complex variable function method. As an application, an antiplane crack problem is further considered by the semi-inverse method, and the closed-form so- lutions of the phonon, phason, and electric fields near the crack tip are obtained. The path-independent integral derived from the conservation integral equals the energy release rate.

关键词： quasicrystals (QCs) piezoelasticity fracture mechanics crack complexvariable method

Mapping Microscale Strain Fields Around a Crack Tip in Molybdenum Via Geometric Phase Analysis and Digital Image Correlation

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Acta Mechanica Solida Sinica 2018年第3期31卷 310-321页

作者： Chunwang Zhao Wencai Li Jijun Li Yongxiang Li Quanlong Liu Lifu Wang Qingyu Hou yongming xing College of Science Inner Mongolia University of Technology College of Arts and Sciences Shanghai Maritime University School of Physical Science and Technology Inner Mongolia University

Uniaxial tension tests were conducted on single-edge-notched tensile specimens of pure molybdenum with a mesh grid pattern in front of the notch. A series of images of crack initialization and propagation with a distorted mesh grid pattern were obtained by means of in situ scanning electron microscopy. Strain fields around the crack tip were mapped successively using geometric phase analysis and digital image correlation techniques, and then compared with the predictions obtained through linear elastic fracture mechanics （LEFM）. The comparison shows that the measured strain distribution ahead of the crack tip is consistent with the LEFM predictions of up to 25 μm from the crack tip.

关键词： Crack Strain field Geometric phase analysis Digital image correlation

纳米SiO_2对钢纤维/混凝土高温后力学性能及微观结构的影响

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复合材料学报 2013年第3期30卷 133-141页

作者：燕兰邢永明内蒙古工业大学理学院呼和浩特010051 呼和浩特职业学院建筑工程学院呼和浩特010058

研究了掺纳米SiO2的钢纤维混凝土(NSFC)、钢纤维混凝土(SFRC)和普通混凝土(NC)三种材料在不同加热温度后的抗压、劈裂和抗折强度等力学性能,对不同温度热处理后的微观结构进行了SEM分析,对钢纤维与过渡区界面的相结构进行了XRD分析。结... 详细信息

研究了掺纳米SiO2的钢纤维混凝土(NSFC)、钢纤维混凝土(SFRC)和普通混凝土(NC)三种材料在不同加热温度后的抗压、劈裂和抗折强度等力学性能,对不同温度热处理后的微观结构进行了SEM分析,对钢纤维与过渡区界面的相结构进行了XRD分析。结果表明:在测试温度范围内,NSFC的抗压、劈裂和抗折强度均高于SFRC和NC的强度,且在400℃时达到最大值。在常温下,NSFC的抗压、劈裂和抗折强度较NC分别提高27.01%、63.28%和54.12%,400℃高温热处理后比NC分别高35.09%、84.62%和87.23%;SEM分析表明,在钢纤维与过渡区的界面处,致密度提高,显微硬度提高。由于固相反应,使界面区结构发生变化,在钢纤维表层形成扩散渗透层(白亮层),即化合物层,呈锯齿状,XRD分析证明,白亮层主要由FeSi2和复杂的水化硅酸钙组成,从而增强了钢纤维与基体的粘结力,提高了混凝土的高温力学性能。

关键词：钢纤维混凝土力学性能高温纳米SiO2 微观结构

单轴应变对CuO光吸收谱影响的密度泛函理论研究

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功能材料 2019年第1期50卷 1188-1191页

作者：陈余邢永明内蒙古工业大学理学院呼和浩特010051

基于密度泛函理论计算了单轴应变对CuO吸收谱的影响。在可见光范围内,施加负应变时,吸收峰呈现出蓝移现象;施加正应变时,吸收峰呈现出红移现象;εz增加到6%以后,吸收谱不存在吸收峰。在红外光范围内:施加负应变时,εx造成吸收峰呈现红... 详细信息

基于密度泛函理论计算了单轴应变对CuO吸收谱的影响。在可见光范围内,施加负应变时,吸收峰呈现出蓝移现象;施加正应变时,吸收峰呈现出红移现象;εz增加到6%以后,吸收谱不存在吸收峰。在红外光范围内:施加负应变时,εx造成吸收峰呈现红移现象,εz造成吸收峰呈现蓝移现象;施加正应变时,εy造成吸收峰呈现红移现象,εz造成吸收峰呈现蓝移现象;εx增加到4%以后,吸收谱不存在吸收峰。

关键词：氧化铜密度泛函理论吸收谱吸收峰

基于数字散斑相关法的紫外老化沥青混合料界面开裂特性

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复合材料学报 2016年第4期33卷 732-740页

作者：王岚弓宁宁邢永明内蒙古工业大学土木工程学院呼和浩特010051

利用数字图像相关技术(DSCM)针对紫外光老化的沥青混合料(HMA)半圆试件弯拉试验中裂纹产生及扩展规律从细观角度进行表征,运用Vic-3D分析软件对沥青混合料半圆试件进行全场位移、应变计算,得到试件破坏过程的位移场、应变场。结果表明:... 详细信息

利用数字图像相关技术(DSCM)针对紫外光老化的沥青混合料(HMA)半圆试件弯拉试验中裂纹产生及扩展规律从细观角度进行表征,运用Vic-3D分析软件对沥青混合料半圆试件进行全场位移、应变计算,得到试件破坏过程的位移场、应变场。结果表明:通过对紫外光照的沥青胶浆、集料及界面水平方向应变场的对比分析,发现界面为沥青混合料最薄弱处,最易产生裂纹;进一步通过水平方向应变随载荷变化曲线的变化对HMA开裂时间进行分析,可以更好地将HMA微裂缝开裂时间与宏观裂缝开裂时间加以区分,且紫外老化后的HMA试样界面开裂时间明显缩短。同时,将相同的紫外老化前后的橡胶粉(CR)改性HMA试样与苯乙烯-丁二烯-苯乙烯(SBS)改性HMA试样的位移随载荷变化规律进行对比发现,经紫外老化后的CR改性HMA比紫外老化后SBS改性HMA具有更强的抗开裂能力及持荷能力。

关键词：沥青混合料紫外光老化数字散斑相关法裂缝断裂韧度界面

静水压力对Al14Mn2P16磁光性质影响的密度泛函理论研究

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计算物理 2020年第2期37卷 231-239页

作者：陈余邢永明内蒙古工业大学理学院内蒙古呼和浩特010051

采用第一性原理,研究不同静水压力(0~20 GPa)下Al14Mn2P16的弹性与磁光性质.计算得到基态是铁磁态.弹性稳定性判据表明该体系是稳定的.研究发现磁矩随静水压力的增加而减小.静水压力低于5 GPa时,居里温度达到184 K,随着静水压力的增加... 详细信息

采用第一性原理,研究不同静水压力(0~20 GPa)下Al14Mn2P16的弹性与磁光性质.计算得到基态是铁磁态.弹性稳定性判据表明该体系是稳定的.研究发现磁矩随静水压力的增加而减小.静水压力低于5 GPa时,居里温度达到184 K,随着静水压力的增加略有下降;有趣的是,当静水压力高于5 GPa时,随着静水压力的增加,居里温度急剧下降,在18 GPa时消失.同时还发现随静水压力的增加可见光范围的吸收峰有明显的蓝移,当静水压力达到20 GPa时,可见光范围的吸收峰消失.

关键词：稀磁半导体居里温度静水压力密度泛函理论