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EFFECT OF REVERT RECYCLE TIMES ON MICROSTRUCTURE AND FATIGUE PROPERTIES IN COBALT BASE SUPERALLOY K640S

T.L. Wang 1 , 2) , J.T. Guo 1) , D.S. Xia 2) , Y.Wang 1) and H.C. Yang 2) 1) Institute of Metal Research , Chinese Academy of Science , Shenyang 110015 , China 2) Material and Metallurgical Institute Northeastern University , Shenyang 110006 , China

金属学报(英文版)

Effect of revert cycles on microstructure and fatigue properties of cast cobalt base superalloy K640S has been investigated. The results show that: at 70 times of cool heat cycles, there were microcracks found in seven times revert and ten times revert. With the increasing of thermal fatigue cycles, the crack of revert grows a little faster than virgin. When the cycle time reaches 200, the crack length for both virgin and reverts have been as long as 2mm. The low cycle fatigue life has no remarkable change, with the increase of revert cycles at 815℃, 360MPa ,0 5Hz. With the times of cycles increasing, it is found that the content of impurity and gas in alloy change a little, and there is no obvious change for dendrite microstructure.

关键词: revert , null , null , null , null

D2、M2S5模具扁钢脱碳特性实验研究

赵德文 , 郭长武 , 刘相华 , 王国栋 , 徐辉 , 戴建明

钢铁

开展了在空气和氮气两种气氛下,采用Gleeble-1500热模拟机与普通电炉两种加热方式、不同加热温度、加热时间对D2、M2S5钢脱碳层深度影响的试验研究。依据试验结果,结合现场实际制定了较为合理的生产工艺并在现场成功应用,使上述模具扁钢脱碳层指标达到了美国ASTM-A681技术标准。

关键词: 脱碳层深度 , 模具扁钢 , ASTM-A681

Energy levels of the d*(8) electron and d*(2) hole system

Physical Review B

In the investigation of the optical and magnetic properties of the semiconductors containing transition-metal ions, the one-electron orbital cannot be treated with a pure d orbital because of a strong covalence. This paper presents the energy matrix of the d*(8) and d*(2) (d* means a modified d function) system, in which the covalence is described by two covalent factors. The differences between the matrix diagonal elements of the t(2)(m)e(n) term of the d*(8) system and the t(2)(6-m)e(4-n) term of the d*(2) system vary with m and n. The d(N) electron system can be explained with the d(10-N) hole system because the difference between the energy matrix of the d(N) and d(10-N) systems has a fixed value. However, this kind of simple relation does not exist for the d*(N) and d*(10-N) systems when the covalence is considered. A numerical calculation shows that the variation of the energy levels with the covalence for Ni2+ in the d*(8) electron system is larger than that in the d*(2) hole system. The calculated energy levels obtained from the d*(8) matrix are in good agreement with the experimental data of the Ni2+ ion for ZnS:Ni and ZnSe:Ni. This suggests that the d*(8) electron system instead of the d*(2) hole system should be used in the investigation of optical and magnetic properties of semiconductor containing Ni2+ ions.

关键词: zns-ni;absorption;vanadium;impurities;spectra;ions

同位旋效应对F同位素s-d能级间隙的影响

郭艳青 , 任中洲

原子核物理评论

在单粒子势模型的框架下,计算了O同位素和F同位素的基态和某些低激发态的能级值、均方根半径值及密度分布.通过在伍兹-萨克逊势中引入同位旋依赖项,研究了同位旋效应对F同位素s-d能级间隙的影响.理论计算得到的均方根半径值和自旋宇称值与实验结果一致.尤其是,理论计算能够实现16F,15F和14F中2s1/2与1d5/2质子能级间的反转,且F同位素中s-d质子能级间隙及其整体变化趋势与已知实验结果符合较好.此外,理论结果表明12F的(1/2)+第一激发态为单质子晕态.

关键词: 同位旋效应 , 能级反转 , 质子晕

S-D系统的统一模型与稀磁合金的电子比热

陈丽 , 韩福祥

低温物理学报 doi:10.3969/j.issn.1000-3258.2000.01.013

本文采用Anderson s-d混合模型和s-d交换模型,讨论了磁性杂质溶入金属后,对稀磁合金比热的影响,并对Cd-Mn合金进行了定量的讨论.

关键词:

铁基超导体Minimum模型中的d波和扩展s

车玮玮 , 苏希玉 , 王梅

低温物理学报

对比研究了Minimum模型中d-波配对和扩展s-波配对的基本性质.结果表明,超导序参量按类BCS关系随温度变化,重整化参数t对超导有抑制作用,当t足够大时,超导消失,系统进入正常金属相.此外,讨论了超导序参量随不同参量的变化关系.对于d波,系统有稳定态;而对于扩展s波,系统则没有稳定态.

关键词: Minimum模型 , d-波 , 扩展s-波 , 铁基超导体

A possible mechanism for quasi-two-dimensional ferromagnetism: The spectrum gap induced by s-d exchange interaction

Journal of Physics-Condensed Matter

A quasi-two-dimensional magnetic system is studied in which magnetic atoms are confined in the two-dimensional plane but the conduction electrons are in fact three-dimensional. By virtue of spin-wave theory, we find that a spectrum gap can be formed at the bottom of the spin-wave spectrum, induced by the s-d exchange interaction between conduction electrons and magnetic localized electrons. Thus, a new possible mechanism is proposed for two-dimensional ferromagnetic order at finite temperature.

关键词: ultrathin films;magnetoresistance;superlattices;magnetization;anisotropy;magnetism

S-D系统的统一模型与稀磁合金的热导率和热电势

陈丽

低温物理学报 doi:10.3969/j.issn.1000-3258.2001.02.012

本文采用Anderson s-d混合模型和s-d交换模型,讨论了磁性杂质溶入金属后,对稀磁合金热导率和热电势的影响,并对Cd-Mn合金进行了定量的讨论.

关键词:

2D12铝合金腐蚀性能研究

孙志华 , 刘明辉 , 张晓云 , 高健 , 陆峰 , 戴立金

航空材料学报 doi:10.3969/j.issn.1005-5053.2006.03.062

对不同规格2D12铝合金进行晶间腐蚀、剥蚀和应力腐蚀性能测定.研究表明,2D12铝合金自然时效(T4)状态具有晶间腐蚀和剥落腐蚀倾向,2D12铝合金S-L方向比S-T方向的抗应力腐蚀的性能低,应力腐蚀开裂门槛应力强度因子分别为22.6和27.1 MPa·m1/2,这与C环应力腐蚀结果一致,断口呈现典型的沿晶断裂特征.

关键词: 2D12铝合金 , 晶间腐蚀 , 剥蚀 , 应力腐蚀

基于DSP和S1D13305的EL屏显示控制系统设计

王兆伟 , 李士钊

液晶与显示 doi:10.3788/YJYXS20142903.0389

针对野外恶劣使用环境,设计了一种环境适应性强的显示控制系统.该系统采用基于DSP和S1D13305控制EL显示屏的设计方案,从软硬件两方面阐述了DSP和显示控制芯片之间的接口电路和设计方法,解决了显示控制芯片内部字库内容单一的问题,并给出了系统设置和显示控制芯片初始化程序,开发了显示驱动模块.经过实战考核和应用,该显示系统在野外恶劣环境中工作稳定,显示效果良好.该显示系统达到了预期效果.

关键词: 控制 , DSP , S1D13305 , EL显示屏

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