YANG Jilian ZHANG Baisheng JIN Lan DING Yongfan YE Chuntar Institute of Atomic Energy
,
Beijing
,
China YANG Yingchang
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KONG Linshu Associate Professor
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P.O.Box 275-80
,
Beijing 102413
,
China
金属学报(英文版)
Neutron diffraction measurements on Nd2(Fe0,Si0 ,)14B at room temperature and 77 K were performed. Data analysis using profile refinement was carried out. The results show that at room temperature Si atoms occupy preferentially 4c, 8j, and I6k2 sites, and the magnetic moments of bath Nd and Fe are parallel to C-axis. At 77 K, the site occupations remain unchanged as in room temperature, while the calculated Nd magnetic moment direction has an angular deviation of 37.8 ° from C-axis.
关键词:
neutron diffraction
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null
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null
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null
Solid State Communications
Considering the image potential, we calculate the binding energies of a shallow donor impurity placed on the centre of a quantum box using the variational approach. The results we have obtained show that there is a great difference of the effects of image potential between the cases including impurity ion image potential and including the image potentials of impurity ion and electron simultaneously. The results also show that the image potential is important, especially when the dimensions of quantum box become small.
关键词:
well;gaas-ga1-xalxas;states
毛斐
,
吴振兴
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汤皎宁
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王涵
,
刘正楷
,
龚晓钟
材料热处理学报
对N型Si80Ge20(P4)x及P型Si80Ge20Bx固溶体合金的化学计量比进行了研究,采用已总结出的最佳工艺条件,制备了一系列N型、P型固溶体合金,并比较了各系列样品的热电性能.结果表明,x=1.5的N型Si80Ge20(P4)x固溶体合金具备良好的热电性能,与未掺杂Si80Ge20固溶体合金相比,最高热电优值ZT为0.651,提高了3.34倍.x=1.5的P型Si80Ge20Bx固溶体合金也具备较佳的热电性能,最高热电优值(ZT)值为0.538.
关键词:
热电材料
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Si80Ge20
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粉末冶金
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热电性能
王秀民
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杜建平
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仲为为
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王培
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胡松青
腐蚀与防护
采用高温高压釜模拟热力采油的蒸汽环境,现场取材对N80和P110两种材质进行了腐蚀试验.采用扫描电子显微镜(SEM)和X射线衍射(XRD)等方法研究了腐蚀产物膜的形貌和化学成分,并研究了高温高压混和蒸汽下的腐蚀机理.结果表明,高温高压混合蒸汽对注汽管柱的腐蚀非常严重,O2、CO2均是重要的腐蚀因素;O2腐蚀产物晶粒细小,CO2腐蚀产物晶粒粗大;150～250℃时,随温度升高O2腐蚀速率呈下降趋势,而CO2腐蚀速率变化不大;250～300℃时,随温度升高O2、CO2腐蚀速率均急剧增大.
关键词:
注汽管柱
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O2腐蚀
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CO2腐蚀
Zeitschrift Fur Metallkunde
The eutectic crystallization process of an amorphous Ni80P20 alloy was monitored by using electrical resistivity measurements (ERM). Upon heating the amorphous sample at constant rates. three distinct processes can be identified from the measured resistance variation with temperature during the crystallization including (i) crystal nucleation, (ii) subsequent growth of crystal nuclei, and (iii) coarsening of the crystallites. These features were verified by microscopy observations as well as the pre-annealing treatments. The activation energies for the crystal nucleation and growth determined from the ERM data agree satisfactorily with the literature data. The results indicated that the ERM is a very sensitive method in detecting detailed information during the early stage of crystallization from amorphous alloys.
关键词:
metallic glasses;temperature;energies;growth
K.S. Guan
金属学报(英文版)
Atomic growth process and structure of Amorphous Electroless Coating have beenstudied, using Monte-Carlo simulation method. The simulation results of amorphousNi80P20 coating show that PDFs are in accordance with practical values. The mi-grations of adatoms in coating's growth are different from that of solidification ofamorphous materials. In some cases, the migrated adatoms in the process of growthof amorphous coating are not enough to occupy all vacancies and traps, so the amor-phous coating is micro-porous. The immovable probability k and the largest migrationdistance of adatoms, which lie on the electroless bath components, affect the PDF,volume density and microporosity remarkably.
关键词:
electroless Ni-P alloy
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null
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null
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null
L. H. Lang
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D. C. Kang
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S. H. Zhang
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Z. R. Wang
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S. J. Yuan
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K. B. Nielsen and J. Dancket 1) Department of Materials Engineering
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Harbin Institute of Technology
,
Harbin 150001
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China 2) Aalberg University
,
Denmark
金属学报(英文版)
In this paper, the forming features of tapered rectangular box during hydrodynamic deep drawing are studied by means of FEM.The effect rules of square blank corner corner amount on body wrinkling are recognized and corresponding methods are discussed. At last, the results of FEM are verified by experi- ment.
关键词:
sheet metal forming
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null
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null
郭秀辉
钢铁研究
为保证莱钢Q275D热轧H型钢极限规格的-20℃冲击功值满足GB/T 700-2006要求,采用Nb微合金化结合再结晶控轧工艺试制了极限规格H400 mm× 200 mm×8 mm×13 mm的Q275D热轧H型钢.结果表明:试制产品的上屈服强度为360～368 MPa,抗拉强度为480～500 MPa,伸长率为32.5 ％～33.0％,平均冲击功为154～233 J,各项性能指标满足标准要求.
关键词:
热轧H型钢
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再结晶控制轧制
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Nb微合金化
景财良
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刘延强
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宋佳友
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王胜东
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彭国仲
中国冶金
doi:10.13228/j.boyuan.issn1006-9356.20150155
针对国内某厂在轧制厚规格S275JR钢卷过程中在钢卷中心位置附近出现了大量裂纹缺陷问题,通过对该缺陷宏观形貌、化学成分、金相组织等进行研究分析后,确定了板卷表面裂纹缺陷是由钢坯皮下微裂纹造成的.基于此分析对S275JR生产过程中的硫质量分数、过热度、结晶器冷却强度与保护渣进行了优化.工业实践表明,工艺调整后钢卷表面裂纹缺陷由12％降低到0.93％.
关键词:
厚规格
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表面裂纹
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钢卷
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皮下微裂纹
郭秀辉
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杜传治
,
李超
钢铁研究
针对莱钢特厚规格Q275D热轧H型钢纵向低温冲击性能不合格的问题,采用金相显微镜和扫描电镜对其显微组织进行了分析,结果表明:混晶组织是造成低温冲击性能不合格的主要原因.根据莱钢现有设备,通过优化成分设计和控制轧制工艺参数,使得此规格H型钢晶粒尺寸细小均匀,-20 ℃纵向V型冲击功平均值大于160 J,满足相应标准要求.
关键词:
Q275D
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V-Ti微合金化
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再结晶控制轧制
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特厚规格H型钢
