DONG Jianxin XIE Wei~* XU Zhichao XIE Xishan ZHANG Shouhua University of Science and Technology Beijing
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Beijing
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China doctorate student P.O.Box 604
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University of Science and Technology Beijing
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Beijing 100083
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China
金属学报(英文版)
Micro-alloying of Mg,ranged from 30 to 70 ppm,may improve the high temperature ductility,stress rupture,especially,certain important mechanical properties,such as cyclic stress rupture,creep/fatigue interaction and crack propagation rate.The quantity, morphology and distribution of δ-phase may obviously influence the notched cyclic stress rup- ture life.The relevant microstructure shows that the Mg may also influence to certain extent on the feature of δ-phase.Thus,to keep the Mg and δ-phase under control may further im- prove the mechanical properties of alloy GH169.
关键词:
superalloy GH169
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null
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null
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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
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
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Harbin 150001
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China 2) Aalberg University
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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
Qunqiang FU
材料科学技术（英文）
At first, a series of finite element method (FEM) simulation tests were used to find the critical forming conditions of hot-galvanized sheet steel during the rectangular box drawing processing when constant blank holder forces were applied. According the test results, the reasonable alteration scope of initial variable blank holder force (VBHF) was as 1.9~2.3 T. Then, based on the test productions of blank holder force, 12 typical VBHF curves were applied to perform the simulation tests by the simulation software of DYNAFORM. The simulation test results showed that VBHF had great effects on drawing formability of hot-galvanized sheet steel during the rectangular box drawing. However, the different VBHF curves were applied to control the whole drawing and it would get great different effects. At the same tine, the VBHF had great effects on the maximum thick thinning ratio, but had little effect on the maximum thick incrassation ratio. So, reasonable application of the VBHF would greatly decrease the fractures. When the VBHF profile is taken as curve L, the best effect of drawing formability could be obtained. When curve I is used, contrary effect could be gotten. The other types of curves would cause effects between above two types of VBHF curves. Finally, the actual tests were applied to check the validity of the FEM simulation tests. The results show that the FEM simulation tests are good ways for predicting and optimizing the VBHF.
关键词:
Drawing process
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变压边力
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热镀锌钢板
Journal of Alloys and Compounds
The subsolidus phase relations in the system La2O3-B2O3-P2O5 were investigated. The system can be divided into 12 three-phase regions. There are nine binary compounds and one ternary compound in this system. The ternary compound La7O6(BO3)(PO4)(2) has a monoclinic structure, space groups P2(1)/n, with lattice constants a = 7.0172 Angstrom, b = 17.9125 Angstrom, c = 12.6500 Angstrom, beta = 97.516 degrees, V = 1576.39 Angstrom(3), and Z = 4.
关键词:
La2O3-B-3-B2O3-P2O5 system;phase relations;ternary compounds
LIANG Yong LI Ruiguo Institute of Metal Research
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Academia Sinica
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Shenyang 110015
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ChinaInstitute of Corrosion and Protection of Metals
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Aademia Sinica
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Shenyang
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110015
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China
材料科学技术（英文）
Recent advances in laser coating technology including laser cladding,laser surface alloying and laser vapour deposition in China are reviewed in this paper.
关键词:
laser
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null
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null
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null
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null
陈玮
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姚长江
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尹周澜
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刘新红
耐火材料
doi:10.3969/j.issn.1001-1935.2008.04.009
分别对反应前后的p-Al2O3进行XRD及SEM分析,确定反应前后Al2O3的物相及显微结构变化;测定加入添加剂前后浆体温度与时间的关系,从而确定添加剂对p-Al2O3水化速度的影响;测定加入添加剂前后浆体的黏度变化,从而测定出添加剂对p-Al2O3水化过程的影响.结果表明:1)p-Al2O3属于无定形态;2)在没有添加剂的情况下,p-Al2O3的水化速率很快,同时释放出大量热量,水化产物主要是一水软铝石、三水铝石和拜耳石;3)加入碳酸钠及六偏磷酸钠的混合物为添加剂后,p-Al2O3的水化速率显著降低,释放出的热量显著降低,水化产物主要是一水软铝石.
关键词:
p - 氧化铝
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水化硬化
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不定形耐火材料
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结合剂
杨迈之
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陈利
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蔡生民
中国腐蚀与防护学报
采用光电化学方法对纯铁在ｐＨ＝８．４的硼酸－硼砂缓冲液中的孔蚀现象及缓蚀剂ＰＣ－６０４的作用进行了研究。结果表明，加入不同量的缓蚀剂后，铁表面饨化膜的禁带宽度没有发生变化，但是光电流信号却随缓蚀剂量的增加而增大了。从光电流暂态谱的研究中首次提出了钝化膜的膜参数的概念，并用以衡量钝化膜的抗孔蚀能力。
关键词:
光电化学
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Iron
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Pitting
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Inhibitor
