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Acta Metallurgica Sinica(English Letters) 2022年第12期35卷 2007-2013页

作者： y.N.Zan X.Lei J.f.Zhang D.wang q.Z.wang b.L.Xiao Z.y.Ma Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shi-changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.LtdBejing 100840China

b4c reinforced Al composites are widely used as neutron absorbing materials(NAMs)due to excellent neutron absorbing efficiency,however,such NAMs exhibit poor high-temperature *** meet the requirement for structure-function integration,NAMs with enhanced high-temperature mechanical properties are *** this work,a novel(b4 c+Al_(2)O_(3))/Al NAM with netlike distribution of Al_(2)O_(3)was fabricated by powder metallurgy method and subjected to high-temperature tensile creep *** was shown that the creep resistance was enhanced by several orders of magnitude via the addition of only2.1 vol.%netlike-distributed Al_(2)O_(3).(b_(4)c+Al_(2)O_(3))/Al exhibited high apparent stress exponents ranging from 16 to 25 and high apparent activation energy of 364 kJ/*** creep behaviour could be rationalized using the substructure-invariant model and its rupture behaviour could be described by the Dobes-Milicka equation.

关键词： Neutron absorber material Al matrix composite Tensile creep b_(4)c/Al

wIDE-bAND LASER cLADDING: wEAR AND cORROSION RESISTANcE Of A Ni-bASED ALLOy

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Acta Metallurgica Sinica(English Letters) 1997年第5期10卷 445-452页

作者： Pan, q.y. Huang, w.D. Li, y.M. Lin, X. Zhou, y.H. yang, X.c. Northwestern Polytechnical Univ Xi'an China

A novel wide-band laser cladding system, with high rate of cladding, has been developed in the present work. The system mainly consisted of a 5kw cO2 laser, an automatic powder feeder and a wide-band scanning rotative polygon mirror which can produce a linear or rectangular focused laser beam. Using this system, a Ni-cr-Si-b alloy powder was cladded on the surface of type 321 austenitic stainless steel in order to improve its wear and corrosion resistance. The pitting corrosion, high temperature oxidation and wear tests were conducted in order to evaluate the properties of the laser cladded layer. The results demonstrated that the cladded layer can significantly improve the adhesive wear and pitting corrosion resistance of the substrate. Moreover, the cladded layer exhibited good oxidation resistance, which is almost the same as that of GMR-235D Ni-based superalloy.

关键词： boron chromium alloys cladding (coating) Laser applications Nickel alloys Silicon alloys wear resistance

MODIfIcATION Of SURfAcE MEcHANIcAL PROPERTIES Of POLycARbONATE by b^+ AND O^+ IONS IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 33-38页

作者： S.D. yao c. Sun S.q. Zhou c.c. Sun y.H. Lu L. Huang A. Vantomme q. Zhao G. Langouche Sch. of Phys. Peking Univ. Beijing 100871 China

by implanting b+ and O+ ions respectively into polycarbonate (Pc) plates, the surface mechanical properties of Pc have been improved. Measurement by Nano Indenter II showed that the hardness of samples increased 7-25 times than that before implantation; and the modulus of elasticity raised 2-5 times. The wear-resistance was tested by ball crusher; the width and depth of the wear-streak decreased by 1/3-1/2 or even more. The structure, deformation and appearance were analyzed by using Micro-fTIR Spectra, EScA method and the steps instrument. These analyses showed that the structure of Pc had been modified: a series of new cross-linking yielded, it depends on the Linear Energy Transition (LET) of implanted ions in the high polymer compounds.

关键词： polycarbonate ion implantation surface modification

fundamental Research on convective Heat Transfer in Electronic cooling Technology

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Journal of Thermal Science 1992年第1期1卷 30-40页

作者： c.f.Ma y.P.can y.q.Tian D.H.Lei beijing Polytechnic University Beijing 100022China

During the past six years comprehensive research programs have been conducted at the beijing Polytechnic University to provide a better understanding of heat transfer characteristics of existing and condidate cool- ing techniques for electronic and microelectronic *** paper provides a review and summary of the programs with emphasis on direct liquid *** in this review are the heat transfer investigations related to the following cooling modes:liquid free,mixed and forced convection,liquid jet impingement,flowing liquid film cooling,pool boiling,spray cooling,foreign gas jet impingement in liquid pool,and forced convection air-cooling.

关键词： convective heat transfer electronic cooling technology cooling modes.

An effective approach for bonding of TZM and Nb-Zr system:Microstructure evolution,mechanical properties,and bonding mechanism

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Journal of Materials Science & Technology 2021年第25期84卷 16-26页

作者： Z.w.yang J.M.Lin J.f.Zhang q.w.qiu y.wang D.P.wang J.Song Tianjin Key Lab of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300072China Department of Mining and Materials Engineering McGill UniversityMontréalQuébecH3A 0C5Canada

A novel method of liquid metallic film(LMf)bonding was developed to join titanium zirconium molybdenum alloy(TZM)and Nb-Zr alloy with a Ni *** this method,a Ni-Zr liquid phase was formed by the eutectic reaction and then squeezed out from the gap due to a transient pressure,leaving an *** not only achieved a reliable metallurgical bonding but also served as a transition layer between TZM and Nb-Zr alloy to reduce the mismatch between them thus further improving its *** bonding mechanism of the TZM and Nb-Zr system was discussed based on theoretical calculation and high-resolution microscopy *** advantages of this method were established by comparing the microstructure and mechanical properties of LMf bonded joints with that of traditional contact-reaction brazing and direct diffusion ***,the feasibility of the LMf bonding method was also demonstrated by the reliable joining of other high-temperature and immiscible systems.

关键词： bonding Titanium zirconium molybdenum alloy(TZM) Diffusion Microstructure Mechanical properties

A NOVEL SyNTHETIc METHOD fOR THE cLUSTERS feco_2(cO)_9- (RccR)(R=MeO_2c,EtO_2c).X-RAy cRySTAL STRUcTURE ANALySESOf THE cLUSTERS feco_2(cO)_9(MeO_2ccccO_2Me) and co_4(cO)_(10)-(EtO_2ccccO_2Et)

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chinese chemical Letters 1996年第6期7卷 585-588页

作者： wu H.P. yin y.q. yu K.b. Huang X.y. Lanzhou Inst. of chemical Physics Chinese Academy of Sciences Lanzhou 730000 chengdu Anal. Determination center Chinese Academy of Sciences Chengdu 610041 fuzhou Inst. Res. Struct. of Matter Chinese Academy of Sciences State Key Lab. of Struct. Chemistry Fuzhou 350002

A novel synthetic method for the clusters feco2(cO)9(RccR)(R=MeO2c,MeO2c), which isthe reaction of co4(cO)10(RccR) with Na2[fe(cO)4], have been found by studying on tile thermal reactionbetween Rcco3(cO)9 with Na2[fe(cO)4]. X-ray crystal structural determinations have been made for theclusters feco2(cO)9(MeO2ccccO2Me) and co4(cO)10(EtO2ccccO2Et)

关键词： cO feco2 RccR ANALySES cLUSTERS

EffEcTS Of HDDR PROcESS ON STRUcTURE AND MAGNETIc PROPERTIES Of Nd(fe,Ti)_(12)N_δ PREPARED by MEcHANIcAL ALLOyING

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Acta Metallurgica Sinica(English Letters) 1998年第1期11卷 68-78页

作者： b.Zcui X.K.Sun X.G.Zhao w.Liu q.f.Xiao T.Zhao Z.D.Zhang y.c.Sui chinese Acad of Sciences Shenyang China

The effects of the hydrogenation-disproportionation-desorption-recombination (HDDR) process on the structure and the magnetic properties of the mechanical alloying (MA) prepared Nd8fe84 Ti8 alloy and its nitride counterpart have been studied in detail. It has been found that Nd(fe, Ti)12Hδ is formed in the temperature range from 300 to 550°℃. The disproportionation is ready to start at 550°℃ and is complete at 960°℃.The desorption and the recombination are almost synchronized. The phase of Nd(fe,Ti)7 is formed at 750°℃ during the HDDR treatment. with increasing temperature of HDDR process, the metastable structure of Tbcu7 type is gradually transformed into the structure of ThMn12 type. The intrinsic coercivity and the maximum magnetic energy product increase with increasing temperature of HDDR process.

关键词： Nd(fe Ti)_(12)N_δ compound,magnetic property hydrogenation

Improved mechanical properties and strengthening mechanism with the altered precipitate orientation in magnesium alloys

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Journal of Magnesium and Alloys 2022年第5期10卷 1256-1267页

作者： y.J.wan y.Zeng y.c.Dou D.c.Hu X.y.qian q.Zeng K.X.Sun G.f.quan Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Material Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China college of Materials Science and Engineering Sichuan University of Science and EngineeringZigong 643000China Department of Materials The University of ManchesterOxford RoadManchester M139PLUnited Kingdom

Aging prior to twinning deformation was proposed to alter the precipitate orientation of the plate-shapedβ-MgAlfrom(0002)basal planes(named basal plates)to■prismatic planes(named prismatic plates)in AZ31 Mg *** experimental results showed that the compressive yield strength(cyS)of the sample containing prismatic plates increased 40 MPa and the compression ratio raised by 22%compared to that containing basal *** underlying strengthening mechanism was analyzed via a yield strengthen(yS)model with a function of grain size,precipitate characters(size,oritention,fraction)and Schmid factor(Sf).It revealed that the improvement of cyS was mainly attributed to the altered precipitate orientation and refined grain size produced by twinning ***,the prismatic plates always have a stronger hardening effect on basal slip than basal plates under the same varites of precipitate diameter and ***,the decreased cRSS ratio of prismatic slip to basal slip revealed that the activity of non-basal slip in Mg alloy might be *** activated slip systems provided more mobile dislocations,contributing to the large compression ratio of the Mg rolled sheet with prismatic plates.

关键词： Precipitate orientation Precipitation strengthening Grain boundary strengthening yield strength model

PERSPEcTIVES IN MEcHANIcS Of HETEROGENEOUS SOLIDS

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Acta Mechanica Solida Sinica 2011年第1期24卷 1-26页

作者： c.q. chen J.Z. cui H.L. Duan X.q. feng L.H. He G.K. Hu M.J. Huang y.Z. Huo b.H. Ji b. Liu X.H. Peng H.J. Shi q.P. Sun J.X. wang y.S. wang H.P. Zhao y.P. Zhao q.S. Zheng w.N. Zou Department of Engineering Mechanics AML Tsinghua University Beijing 100084 China Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100190 China State Key Laboratory for Turbulence and complex System and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China cAS Key Laboratory of Mechanical behavior and Design of Materials University of Science and Technology of China Hefei Anhui 230026 China School of Aerospace Engineering Beijing Institute of Technology Beijing 100081 China Institute for Advanced Study Nanchang University Nanchang 330031 China Depariment of Mechanics and Engineering Sciences Fudan University 220 Handa Road Shanghai 200433 China Department of Mechanical Engineering Hong Kong University of Science and Technology Hong KongChina Department of Mechanical Engineering Hong Kong University of Science and Technology Hong Kong China Institute of Engineering Mechanics Beijing Jiaotong University Beijing 100044 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

The Micro- and Nano-mechanics working Group of the chinese Society of Theoretical and Applied Mechanics organized a forum to discuss the perspectives, trends, and directions in mechanics of heterogeneous materials in January 2010. The international journal, Acta Mechanica Solida Sinica, is de- voted to all fields of solid mechanics and relevant disciplines in science, technology, and engineering, with a balanced coverage on analytical, experimental, numerical and applied investigations. On the occasion of the 30TM anniversary of Acta Mechanica Solida Sinica, its editor-in-chief, Professor q.S. Zheng invited some of the forum participants to review the state-of-the-art of mechanics of heterogeneous solids, with a particular emphasis on the recent research development results of chinese scientists. Their reviews are organized into five research areas as reported in different sections of this paper. ~I firstly brings in fo- cus on micro- and nano-mechanics, with regards to several selective topics, including multiscale coupled models and computational methods, nanocrystal superlattices, surface effects, micromechanical damage mechanics, and microstructural evolution of metals and shape memory alloys. ~II shows discussions on multifield coupled mechanical phenomena, e.g., multi-fields actuations of liquid crystal polymer networks, mechanical behavior of materials under radiations, and micromechanics of heterogeneous materials. In ~III, we mainly address the multiscale mechanics of biological nanocomposites, biological adhesive surface mechanics, wetting and dewetting phenomena on microstructured solid surfaces. The phononic crystals and manipulation of elastic waves were elaborated in ~IV. finally, we conclude with a series of perspectives on solid mechanics. This review will set a primary goal of future science research and engineering application on solid mechanics with the effort of social and economic development.

关键词： heterogeneous materials smart materials biological materials multiscale mechanics micro- and nano-mechanics damage and fracture constitutive relation elastic wave surface effects

Influencing mechanism of pre-existing nanoscale Al5fe2 phase on Mg-fe interface in friction stir spot welded Al-free ZK60-q235 joint

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Journal of Materials Science & Technology 2020年第7期42卷 220-228页

作者： R.Z.Xu q.yang D.R.Ni b.L.Xiao c.Z.Liu Z.y.Ma Institute of Metal Research Chinese Academy of SciencesShenyang110016China college of Material Science and Engineering Shenyang Aerospace UniversityShenyang110136China Department of Materials Science and Engineering University of Illinois at Urbana-Champaign1304 W Green StUrbanaIL61801United States fredrick Seitz Materials Research Laboratory University of Illinois at Urbana-Champaign104 S Goodwin AveUrbanaIL61801United States

Al-free ZK60 magnesium (Mg) alloy sheet was selected as substrate material of Mg-steel pinless friction stir spot welding (fSSw), avoiding the effect of the Al element in the substrate on the alloying reaction of Mg-iron (fe) interface. The sound fSSw joint of ZK60 Mg alloy and q235 steel with a hot-dipped aluminum (Al)-containing zinc (Zn) coating was successfully realized. The detailed microstructural examinations proved that Al5fe2 phase at the Mg-fe interface came from the pre-existing Al5fe2 phase in the coating and acted as the transition layer for promoting the metallurgical bonding of Mg and fe. The interfaces with well-matched lattice sites among fe, Al5fe2 and Mg were formed during fSSw. A low energy interface with good match of lattice sites ((002)Al5fe2//(110)fe, [110]Al5fe2//[113]fe) between Al5fe2 and fe was identified. for the interface between Al5fe2 and Mg, an orientation relationship of (622)Al5fe2//(3112)Mgand[158]Al5fe2//[2423]Mg was observed. The tensile-shear load of the ZK60-steel joint could reach 4.6 kN. Moreover, the joint fracture occurred at the interface between the Al5fe2 layer and the Mg alloy substrate, suggesting the brittle fracture characteristic.

关键词： Dissimilar welding friction stir spot welding Magnesium alloys Steels Zinc coating