P. He
金属学报(英文版)
The fuzzy numerical value analysis method is adopted for the first time, which solves the problem of nanometer electro-thermal in filming process. The key technique is embodied by controlling the time distribution, temperature and press in the filming process. The concrete technique of filming is showed by establishing the fuzzy mumbership function of above three indexes, which improves the precision of the materials of nanometer electro-thermal in hot-working. At the same time, the principles of the fuzzy relationship mapping inversion (FRMI) is put forward. Therefore, the standardization and continuity can be met.
关键词:
fuzzy control
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null
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null
P. He
,
J. H. Zhang
,
J. C. Feng and Y. Y. Qian (National Key Laboratory of Advanced Welding Production Technology
,
HIT
,
Harbin 150001
,
China)
金属学报(英文版)
TiAl was diffusion bonded to Ti and TC4 alloy in vacuum furnace. Results showed,at the TiAl-Ti interface,the reaction layer of stratification Ti3Al was formed closest to TiAl base,and the a phase and the α + βphase arised closest to Ti base at 1173K and 1573K respectively. The phase structure of TiAl/ and the phase structure of TiAlwere observed be- tween AiAl and TC4 under respetive bonding temperature.The fiacture at tensile testing occurred in the bond - line, producing very flat fracture surfaces with some pull-out of the TiAl materials.The ultimate tensile strengths of the joint were approximate to γ-TiAl base marterial.
关键词:
diffusion bonding
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null
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null
ZHANG Lei WANG Peixuan TAO Rong MA Ruzhang ZHANG Guoguang University of Science and Technology Beijing
,
Beijing
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China professor
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Department of Materials Physics.University of Science and Technology Beijing.Beijing 100083
,
China
金属学报(英文版)
Nucleation and growth of He bubbles at different annealing temperatures T≤1023 K in stain- less steels HR-2 and SS321,implanted with He~+(40-70 keV.1×10~(16)-6× 10~(17) He~+/cm~2),were ohserved under TEM.T=0.45T_m seems to be a transition temperature.The He bubbles continue mainly their nucleation at 0.3T_m< T<0.45T_m,and grow predominantly at T≥0.45T_m,due probably to migration and coalescence by surface diffusion of metal atoms around the bubbles.The apparent activation energies for the growth are found to he 0.41 and 0.31 eV for HR-2 and SS321 respectively.The bubble density in HR-2 is greater than that in SS321 within whole measuring temperature range,and the onset temperature of rapid swelling is also higher.It is believed that the resistance of HR-2 to He is superior to that fo SS321.
关键词:
stainless steel
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null
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null
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null
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null
冯文天
,
马新文
,
朱小龙
,
张少峰
,
刘惠萍
,
李斌
,
闫顺成
原子核物理评论
利用反应显微成像谱仪对70和100 keV He2+与He原子碰撞转移电离(TI)过程中不同出射角度的电子能谱进行了测量,观测到出射电子能谱具有如下分布特征:出射电子速度分布介于0和入射离子速度νp之间;在不同出射角度电子能谱分布均有一极大值存在,随着出射角度的增大,能谱分布极大值逐渐减小; 当电子出射角度等于45°时,多数电子集中在0 eV附近.上述特征可由低能离子-原子碰撞"准分子"模型进行定性解释.在100 keV He2+-He转移电离出射电子能谱中有靶电子被俘获至散射离子连续态(electron capture to continuum,简称ECC)电子的贡献,这可看做是动力学两步过程的作用.
关键词:
反应显微谱仪
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转移电离
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ECC电子
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"准分子"模型
李悦
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邓爱红
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刘莉
,
王康
,
谢莎
材料研究学报
利用x射线衍射(xRD)和慢正电子束分析(SPBA)技术研究高温退火后含He钛膜的微观结构和钛膜内He相关缺陷的演化.XRD分析表明,高温退火后Ti和Si在高温下发生反应形成稳定的多晶TiSi2化合物,He原子的掺入会影响TiSi2晶体的择优取向,而对TiSi2晶粒尺寸的影响较小.SPBA结果表明,室温下,钛膜内的缺陷浓度或尺寸会随着掺He浓度的增加而增大;高温退火后,当He浓度小于5％(原子分数,下同)时(除2％外),钛膜内的He相关缺陷浓度随着He浓度增加相应地增加.当He浓度增加到14％时,高温会使较高浓度的He原子、He-空位复合体以及小He泡迁移聚集形成一些尺寸较大He泡,而较大He泡周围与He相关的小尺寸缺陷的浓度则会发生相应地减少.
关键词:
金属材料
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含He钛膜
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直流磁控溅射
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He相关缺陷
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XRD
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SPBA
施立群
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金钦华
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刘超卓
,
徐世林
,
周筑颖
原子核物理评论
doi:10.3969/j.issn.1007-4627.2005.01.045
研究了用He/Ar混合溅射气体的直流磁控溅射制备钛膜中He的掺入现象.分析结果表明,大量的He原子(He/Ti原子比高达56%) 被均匀地引入到Ti膜中,He含量可由混合溅射气体的He分量精确控制.通过调节溅射参数,可实现样品中He的低损伤引入.研究还发现,溅射沉积的含氦Ti膜具有较高的He成泡剂量和高的固He能力,这可能是溅射沉积形成了纳米晶Ti膜所致.纳米晶Ti膜较粗晶材料具有很高浓度的He捕陷中心,使He泡密度增大而泡尺寸减小.随He引入量的增加,Ti膜的晶粒尺寸减小,He引起的晶体点阵参数和X射线衍射峰宽度增大,晶体的无序程度增加.
关键词:
氦
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损伤
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泡
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钛膜
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溅射沉积
刘小井
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朱林繁
,
苑震生
,
李文斌
,
成华东
,
徐克尊
原子核物理评论
doi:10.3969/j.issn.1007-4627.2002.02.058
在入射电子能量2 500 eV下测量了He的1 1S→2 1S, 2 1P, 3 1S和3 1P的微分散射截面和广义振子强度, 并与前人的实验和理论结果进行了比较, 认为在此入射电子能量下一阶Born近似对此4个跃迁成立.
关键词:
跃迁
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微分散射截面
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广义振子强度
