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Journal of University of Science and Technology Beijing 2005年第2期12卷 128-133页

作者： JunZhang YuZhang LiLi ChunliWang QingjiangWang YuyinLiu DepartmentofMaterialsScienceandEngineering ShenyangUniversityShenyang110044China AppliedScienceSchool UniversityofScienceandTechnologyBeijingBeijing100083China InstituteofMetalResearch ChineseAcademyofSciencesShenyang110015China

Some experimental α+α2 alloys were prepared by the addition of tin or aluminum elements into Ti-55 alloy. These alloys were designed with varied electron concentration values and named as Sn-rich alloys and Al-rich alloys, respectively. The precipita- tion and growth of α2 ordered phase in the tested alloys under various heat treatment conditions were investigated. Some compari- sons among the experimental results were performed and discussed in detail. Stronger precipitation and growth of α2 ordered phase were caused in Al-rich alloys but relatively weak change in Sn-rich alloys with increasing the electron concentration. The precipita- tion of α2 ordered phase in Al-rich alloys is stronger than that in Sn-rich alloys when the electron concentration value is the same for the two alloys.

关键词： titanium alloy ordered phase electron concentration microstructure

Effects of Alloying Elements on the Volume Fraction of Ordered α_2 Phase Precipitated in Ti-Al-Sn-Zr Alloys

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Journal of Materials Science & Technology 2007年第1期23卷 102-106页

作者： Jun ZHANG Na PENG Xinan WANG Li LI Qingjiang WANG Department of Materials Science and Engineering Shenyang University Shenyang 110044 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

An ideal method has been established for calculating the precipitation of α2 ordered phase in near-α titanium alloys based on the theory on the critical electron concentration for the precipitation of α2 ordered phase in near-α titanium alloys. With complete precipitation of α2 phase in near-α titanium alloys, the alloys can be considered to be composed of two parts：（1） the α2 ordered phase with the stoichiometric atomic ratio of Ti3X; （2） the disorder solid solution with the critical composition in which the α2 ordered phase is just unable to precipitate. By using this method, the volume fractions of α2 ordered phase precipitated in Ti-Al, Ti-Sn, Ti-Al-Sn-Zr alloys with various AI, Sn and/or Zr contents have been calculated. The influences of AI and Sn on the precipitation of α2 ordered phase are discussed. The calculating results show substantial agreement with the experimental ones.

关键词： Ordered α2 phase Precipitation electron concentration Titanium alloys

Modulation of drain current as a function of energies substrate for InP HEMT devices

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Journal of Semiconductors 2018年第11期39卷 31-35页

作者： S.Derrouiche B.Bouazza C.Sayah Laboratory for Materials and Renewable Energies Faculty of Technology University Abou Bekr Belkaid of TlemcenDepartment of Electrical and Electronics Engineering Faculty of Technology University Center Belhadj Bouchaib of Ain-Temouchent Department of Electrical engineering

We present the drain current modulation for an HEMT using the TCAD SILVACO simulation tool with a drift–diffusion model at ambient temperature. The obtained results show that the decreases of substrate energies induce the decreasing of the obtained drain current similarly to the transconductance, which described the device due to increasing the transferred electrons concentration towards the substrate region, consequently to increase the molar fraction where the concentration of transferred electrons increases from 49 × 10;to 65 × 10;cm;when the molar fraction increases from 0.1 to 0.9. On the other hand, the decrease of molar fraction from 0.9 to 0.1 induces the increasing of drain current by 63%, where it increases from 1.1 mA/mm to 3 mA/mm at V;= 0.6 V and V;= 1 V. This fact leads to ensuring the possibility of using the obtained results of this work related to drain current for producing performances devices that brings together the AC characteristics of HEMT with a weak drain current, which is important in the bioengineering domain.

关键词： high electron mobility transistors (HEMT) electron concentration drain current modulation electron injection bio-engineering

Glass formation of ternary Sm-based Sm-Al-Co bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2007年第S1期15卷 50-53页

作者： Jiang Wu1), Qing Wang1), Weirong Chen1), Qingyu Zhang1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of Materials Modification, Dalian University of Technology, Dalian 116024, China 2) International Center of Materials Physics, Chinese Academy of Sciences, Shenyang, 110016, China

Ternary Sm-based Sm-Al-Co alloys at specific compositions designed using an e/a- and cluster-related criteria exhibit high glass forming abilities and form bulk glassy rods of 3 mm in diameter by a copper mold suction-casting method. Four composi- tions of bulk metallic glasses (BMGs) are Sm50Al25Co25, Sm52Al24Co24, Sm54Al23Co23 and Sm56Al22Co22, which all satisfy a constant conduction electron concentration of 1.5. Among them, the BMG exhibiting the largest reduced glass transition temperature (Trg) is Sm50Al25Co25, which reaches 0.648. The glass transition temperature Tg and the onset crystallization temperature Tx of this alloy are respectively 579 and 640 K at a heating rate of 20 K/min.

关键词： Sm-based alloys bulk metallic glasses alloy design cluster line electron concentration

Bulk metallic glasses formed by alloying the Cu_6Zr_5 cluster

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International Journal of Minerals,Metallurgy and Materials 2007年第S1期15卷 39-42页

作者： Yanhui Li1), Qing Wang1), Jiang Wu1), Jianbing Qiang1), and Chuang Dong1,2) 1) State Key Lab of Materials Modification, Dalian University of Technology, Dalian 116024, China 2) International Center of Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China

The bulk metallic glass formation in the Cu-Zr-M ternary systems by alloying of a binary basic Cu6Zr5 cluster was inves- tigated, where M stands for Sn, Mo, Ta, Nb, Ag, Al and Ti. The Cu6Zr5 cluster is a capped Archimedean antiprism that characterizes the local structure of the Cu10Zr7 crystalline phase. This cluster composition almost superposes with Cu-Zr eutectic Cu0.56Zr0.44. A se- ries of alloys along the cluster line (Cu6Zr5)1-xMx were examined for their glass forming abilities. Alloy rods with a diameter of 3 mm were prepared by copper mould suction casting method and analyzed by XRD and thermal analysis. The Cu-Zr based bulk metallic glasses were discovered with minor Nb, Sn, Mo, Ta additions (≤2at%) and Al, Ti, Ag (8at%≤concentration≤9at%). The alloying mechanism was discussed in the light of atomic size, cluster-linking structure and electron concentration factors.

关键词： bulk metallic glasses cluster electron concentration atomic size minor-alloying Cu-Zr alloys

PHASE BOUNDARY OF α_2 PRECIPITATION IN Ti-Al-La TERNARY SYSTEM

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Acta Metallurgica Sinica(English Letters) 1989年第1期2卷 69-72页

作者： YA NG Rui LI Dong WAN Xiaojing Institute of Metal Research,Academia Sinica,Shenyang,China

The phase boundary,of α_2 precipitation at 600℃ in Ti-AI-La ternary system has been de- termined by TEM examination,which shows three kinds of phase regions,namely the single α phase region,the transitional phase region where there is superlattice reflection but no α_2 precipitation,and the α+α_2 region.A point of maximum aluminium content was found to exist on the α/(α+α_2)boundary and the track of the boundary was explained in terms of the internal oxidation of lanthanum and the electron concentration rule for α_2 formation.

关键词： ternary system Ti-Al-La phase boundary α_2 precipitation internal oxidation electron concentration

Maximizing Terahertz Energy Absorption with MXene Absorber

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Nano-Micro Letters 2023年第11期15卷 136-139页

作者： Xinliang Li Hao Luo Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052People’s Republic of China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450052People’s Republic of China

Achieving high absorption in broad terahertz bands has long been challenging for terahertz electromagnetic wave *** in Nature Photonics,Xiao et *** the high absorption approaching the theoretical upper limit across the whole terahertz band of MXene-based terahertz absorbers and,on this basis,constructed an applicable,updated alternating current impedance matching model.

关键词： Terahertz absorption MXene absorber Impedance matching electron concentration Relaxation time