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Acta Mechanica Solida Sinica 2022年第5期35卷 867-879页

作者： Chunyu Meng mingxiang chen Department of Engineering Mechanics School of Civil EngineeringWuhan UniversityWuhan430072China

When the rate of a symmetric second-order symmetric tensor is discussed,the spin of the principal axis is *** paper proposes a method to establish the basis-free expression of the spin in terms of tensor and its rate by making use of the tensor function representation *** proposed method is simple and the expression of the spin established is *** obtain the rate of the isotropic function of a second-order symmetric tensor,the fourth-order tangent tensor needs to be derived,which is the derivative of the tensor function to the second-order *** decomposing the second-order symmetric tensor space into two orthogonal subspaces,the closed-form fourth-order tangent tensor is decomposed into two parts,which are linear mappings in these two orthogonal subspaces,*** two linear mappings are derived in an extremely simple ***,the method proposed in this paper is applied to obtain the expression of the relationship between material logarithmic strain rate and deformation *** whole process is simple and avoids tedious operations.

关键词： Tensor rate Basis-free spin Tensor function rate Orthogonal space decomposition

An anisotropic micromechamcal model for calculation of effective elastic moduli of Ni-based single crystal superalloys

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Science China(Technological Sciences) 2017年第3期60卷 452-458页

作者： LI ShuangYu WU WenPing LI YunLi chen mingxiang Department of Engineering Mechanics School of Civil Engineering Wuhan University Wuhan 430072 China State Key Laboratory of Water Resources & Hydropower Engineering Science Wuhan University Wuhan 430072 China

An anisotropic micromechanical model based on Mori-Tanaka method is developed to calculate the effective elastic moduli of

关键词： Ni-based single crystal superalloys effective elastic moduli Mori-Tanaka method anisotropic inclusion

Effects of grain size on phase transition behavior of nanocrystalline shape memory alloys

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Science China(Technological Sciences) 2014年第4期57卷 671-679页

作者： SUN QingPing ASLAN Ahadi LI MingPeng chen mingxiang Department of Engineering Mechanics Wuhan University Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology

We report recent advances in the experimental and theoretical study of grain size(GS)effects on the thermal and mechanical properties of nanostructured NiTi polycrystalline shape memory alloy(SMA).It is shown that when GS<60 nm,the superelastic stress-strain hysteresis loop area(H)of the polycrystal decreases rapidly with GS and tends to vanish as GS approaches 10 *** the same time,the temperature dependence of the transition stress also decreases with GS and eventually approaches zero,leading to a wide superelastic temperature window and breakdown of the Clausius-Claperyon *** dependence of the stress-strain responses is significantly reduced and the cyclic stability of the material is improved by the *** is proposed that the emergence of such significant changes in the behavior of the material with GS reduction originate from the large increase in the area-to-volume ratios of the nanometer-thick interfaces(grain boundary and Austenite-Martensite(A-M)interface)in the *** particular,with GS reduction,interfacial energy terms will gradually become dominant over the bulk energy of the crystallite,eventually bring fundamental changes in the phase transition responses of the *** strategy leading to the establishment of quantitative relationships among GS,grain boundary,A-M interfaces and the macroscopic responses of the material are outlined.

关键词： grain size effects phase transition behavior grain boundary and austenite-martensite (A-M) interface nanocrystalline NiTi shape memory alloys

Laser spot associated high-saturation phosphor-in-glass film for transmissive and reflective high-brightness laser lighting

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Journal of Advanced Ceramics 2023年第9期12卷 1821-1832页

作者： Zikang Yu Jiuzhou Zhao Qing Wang Yun Mou mingxiang chen Yang Peng School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Integrated Circuits Sun Yat-sen UniversityShenzhen 518107China

Phosphor-in-glass(PiG)film is a promising luminescent material in high-brightness laser lighting for its advantages of high efficiency,outstanding color quality,and low-cost preparation,which must bear high laser power(LP)and laser power density(LPD)simultaneously to enable high-luminance ***,laser spot associated high-saturation PiG film was proposed for transmissive and reflective high-brightness laser *** types of PiG films were prepared by printing and sintering La_(3)Si_(6)N_(11):Ce^(3+)(LSN)phosphor-borosilicate glass pastes on a sapphire substrate(PiG-S)and an AlN substrate(PiG-A),*** PiG films with perfect crystal structure of phosphor were reliably bonded on the *** effects of laser spot areas on the luminescence saturation of LP and LPD were investigated in the PiG *** the increase of laser spot area from 0.5 to 2.5 mm^(2),the LP threshold of PiG films is gradually raised,while the LPD threshold of PiG films is *** PiG-S withstands a high LP of 23.46 W and a high LPD of 20.64 W/mm^(2),enabling white light with a luminous flux of 3677 *** PiG-A withstands a high LP of 41.12 W and a high LPD of 35.56 W/mm^(2),enabling white light with a luminous flux of 2882 ***,the PiG-A maintains lower working temperature compared with the PiG-S,and the temperatures reduce with the increasing laser spot *** results demonstrate that the laser spot associated PiG films realize high saturation thresholds of LP and LPD simultaneously,and enable high luminance for laser lighting.

关键词： phosphor-in-glass(PiG)film white laser lighting high luminescence saturation laser spot regulation opto-thermal performances

TXV Technology:The cornerstone of 3D system-in-packaging

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Science China(Technological Sciences) 2022年第9期65卷 2031-2050页

作者： ZHAO HeRan chen mingxiang PENG Yang WANG Qing KANG Min CAO LiHua School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China The 47th Institute of China Electronics Technology Group Corporation Shenyang 110000China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Shenyang National Laboratory for Materials Science Shenyang 110016China

System-in-packaging(Si P) can realize the integration and miniaturization of electronic devices and it is significant to continue Moore’s ***-X-via(TXV) technology is the cornerstone of 3 D-SiP,which enables the vertical stacking and electrical interconnection of electronic *** originated from through-hole(TH) in PCB substrates and evolved in different substrate materials,such as silicon,glass,ceramic,and *** work provides a comprehensive review of four distinguishing TXV technologies(through silicon via(TSV),through glass via(TGV),through ceramic via(TCV),and through mold via(TMV)),including the fabrication mechanisms,processes,and *** TXV technology has unique characteristics and owns particular processes and *** process methods,key technologies,application fields,and advantages and disadvantages of each TXV technology were *** cutting-edge through-hole process and development direction were reviewed.

关键词： through silicon via(TSV) through ceramic via(TCV) through glass via(TGV) through mold via(TMV) 3D packaging chip stacking interposer

RESEARCH ON EROSION OF SILICON CARBIDE CERAMIC BLADE

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Journal of Wuhan University of Technology(Materials Science) 1997年第Z1期12卷 63-68页

作者：陈家炎 Wuhan University of Technology

In this paper, three linds of silicon carbide ceramic materials are chosen to perform the tests of material erosive wear. The relationship of ambient parameters, abrasive property and target property is studied in these experiments. Some main factors affecting erosive wear rate are determined by analysis of testing results, step wise regression analysis is completed according to the nondimensional quantities obtained by dimensional analysis. Relative hardness (partide to target Hp/Ht and erosion factor (Hpd1/2/Kic) are put for-ward to evaluate erosion property.

关键词： silicon carbide ceramic erosion wear relative hardness erosion factor

Unique sandwich design of high-efficiency heat-conducting phosphor-in-glass film for high-quality laser-driven white lighting

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Journal of Advanced Ceramics 2022年第12期11卷 1889-1900页

作者： Yang PENG Zikang YU Jiuzhou ZHAO Qing WANG Jiaxin LIU Bo SUN Yun MOU mingxiang chen School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Multi-color phosphor-in-glass(PiG)film has been considered as a promising color converter in high-quality laser lighting owing to its outstanding merits of phosphor versatility,tunable luminescence,and simple ***,the opto-thermal properties of PiG film are severely affected by the photon reabsorption and backward scattering of phosphor structure and the heat conduction of ***,a unique sandwich design of phosphor structure was introduced in the multi-color PiG film for high-quality laser *** elaborately synthesizing the borosilicate glass with low glass transition temperature(T_(g)),similar expansion coefficient,and high refractive index(RI),the sandwiched PiGs were prepared by sintering(~600℃)broadband green and red phosphor glass films on the double sides of *** green and red PiG films were tightly coated on the sapphire with no delamination and maintained higher luminescence intensity than raw phosphors at high *** simultaneously coupling photon reabsorption and backward scattering,the sandwiched green PiG film-sapphire-red PiG film(G-S-R PiG)yields a high-quality white light with a high luminous efficacy of 163 lm/W and an excellent color rendering index(CRI)of 85.4 under a laser power of 2.4 W,which are the best comprehensive results yet *** from the ingenious sandwich design with heat-conducting sapphire and thin PiG films,the G-S-R PiG displays low working temperatures(<200℃)under high-power laser *** work reveals the role of sandwiched phosphor structure in photon loss and heat dissipation,which provides a new strategy to design PiG films for high-quality laser lighting.

关键词： laser-driven lighting phosphor-in-glass(PiG)film sandwich structure color quality heat dissipation

Effect of Li and Ti Additions on Lα(Al)+Mg_2Si Pseudobinary Eutectic Reaction

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Journal of Materials Science & Technology 1997年第6期13卷 487-490页

作者： Shengxu ZHAO Shunpu LI Deqian ZHAO mingxiang PAN and Xichen chen(Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China) Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Effect of Li and Ti additions on Lα(AI)+Mg2Si pseudobinary eutectic reaction in ternary Al-Mg-Si system has been investigated by thermoanalysis, directional solidification and metallographic techniques in this study. It has been found that Li addition causes decreasing of the volume fraction of Mg2Si, while a little amount of Ti causes to increasing, which is of a great importance to the adjustment of phase constitution and alloy properties. Doping components have little influence on the eutectic temperature.

关键词： Si Al Mg2Si Pseudobinary Eutectic Reaction Effect of Li and Ti Additions on L Li Ti

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使用主值空间表示的各向同性塑性本构方程

固体力学学报 2009年第4期30卷 346-353页

作者：陈明祥武汉大学土木建筑工程学院武汉430072

针对各向同性材料,在内变量为标量的假定下,应用张量函数表示定理给出了其塑性应变增量的不变性表示,它的3个不可约基张量取决于应力张量、相互正交且共主轴.建立3个基张量构成的张量子空间与三维主值空间的对应关系,将共主轴的张量采... 详细信息

针对各向同性材料,在内变量为标量的假定下,应用张量函数表示定理给出了其塑性应变增量的不变性表示,它的3个不可约基张量取决于应力张量、相互正交且共主轴.建立3个基张量构成的张量子空间与三维主值空间的对应关系,将共主轴的张量采用笛卡尔坐标系中的矢量描述,矢量在不同坐标系下的分量均为张量的一组不可约不变量.定义塑性应变增量对应的矢量为内变量增量,使用张量函数表示理论得到,内变量演化方程除取决于应力对应的矢量和内变量本身外,还取决于应力增量在张量子空间中的投影,该投影就是应力对应矢量的增量,因此,本构方程归结为确定主值空间中矢量之间的关系.最后表明,三维主值空间与张量子空间中的流动法则是等价的.

关键词：内变量不变量 Lode角张量函数表示定理本构方程塑性势流动法则

Mesoscopic characterization and modeling of microcracking in cementitious materials by the extended finite element method

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Theoretical & Applied Mechanics Letters 2014年第4期4卷 1-11页

作者： Junjie Huang mingxiang chen Jian Sun School of Civil Engineering Wuhan University School of Civil Engineering Harbin Institute of Technology

This study develops a mesoscopic framework and methodology for the modeling of microcracks in concrete. A new algorithm is first proposed for the generation of random concrete meso-structure including microcracks and then coupled with the extended finite element method to simulate the heterogeneities and discontinuities present in the meso-structure of concrete. The proposed procedure is verified and exemplified by a series of numerical simulations. The simulation results show that microcracks can exert considerable impact on the fracture performance of concrete. More broadly, this work provides valuable insight into the initiation and propagation mechanism of microcracks in concrete and helps to foster a better understanding of the micro-mechanical behavior of cementitious materials.

关键词： microcracks extended finite element method mesoscopic modeling concrete