P. Zhang
,
J.Z. Cui
,
Y.H. Du and Q.Z. Zhang(Department of Metal Forming
,
Northeastern University
,
Shenyang 110006
,
China)(Department of Mining
,
Northeastern University
,
Shenyang 110006
,
China)
金属学报(英文版)
Artificial neural networks (ANN), being a sophisticated type of information processing system by imitating the neural system of human brain, can be used to investigate the effects of concentration of flux solution, temperature of liquid aluminium, temperture of tools and pressure on thickness of the intermetallic layer at the interface between steel and aluminium under solid-liquid pressure bonding of steel and aluminium perfectly. The optimum thickness has been determined according to the value of the optimum shearing strength.
关键词:
artificial neural network
,
null
,
null
Journal of Physics D-Applied Physics
Magnetic, electronic transport and magneto-transport behaviours of (Co1-xMnx)(2)P (0.55 <= x <= 0.675) compounds have been systematically investigated. A typical metallic-conductivity behaviour is observed in the ferromagnetic compound (Co0.45Mn0.55)(2)P. The increase in the Mn concentration gives rise to dramatic changes in magnetic, electronic transport and magneto-transport behaviours. With increasing temperature, a first-order phase transition from antiferromagnetism to ferromagnetism takes place at about 145 K, 185K and 240K for x = 0.60, 0.625 and 0.65, respectively. (Co0.4Mn0.6)(2)P and (Co0.375Mn0.625)(2)P compounds experience a metal-insulator transition (Anderson transition) with decreasing temperature. An external magnetic field of 5 T strongly influences the Anderson transition, lowering the transition temperature from 80 to 55K for (Co0.4Mn0.6)(2)P and from 115 to 70K for (Co0.375Mn0.625)(2)P. In contrast with this metal-insulator transition, an insulating behaviour appears in the temperature range from 10 to 300K for (Co0.35Mn0.65)(2)P and (Co0.325Mn0.675)(2)P compounds. Below the antiferromagnetic-ferromagnetic transition temperature TAF-F, a metamagnetic transition can be induced by an external magnetic field. The metamagnetic transition is accompanied by a maximum magnetoresistance ratio of -7%, -6.3% or -3.7% at 5 T in the (Co0.4Mn0.6)(2)P, (Co0.375Mn0.625)(2)P or (Co0.35Mn0.65)(2)P compound at 10 K. The mechanisms of magnetoresistive behaviours are discussed in terms of the formation of a super-zone gap in the antiferromagnetic state.
关键词:
metamagnetic-transition;solid solutions;resistivity;systems;magnetoresistance;anomalies;alloys;field
钱建刚
,
滕晓明
,
刘玉芬
,
黄巍
稀有金属材料与工程
利用金相显微镜(OM)、扫描电子显微镜(SEM)及能谱(EDS)等分析测试手段,研究AZ91D镁合金上直接化学电镀Ni-P的沉积过程.结果表明:活化后的表面上不同位置处最初沉积Ni的过程不同.在活化后的块状物上,由于氟化物的溶解,Mg置换出Ni,因此最初"块状物"上只有Ni沉积,没有P.β相和α相边缘则是由于其电位较高,附近的Ni2+得到Mg失去少量电子后还原沉积出高催化活性的Ni核,催化了次亚磷酸钠还原沉积出P和Ni.
关键词:
AZ11D镁合金
,
Ni-P镀层
,
沉积
钟惠妹
,
黄振霞
,
许彩霞
,
陈震
电镀与涂饰
doi:10.3969/j.issn.1004-227X.2005.06.003
在有机高分子聚合物薄膜,如投影仪专用胶片上超声波化学镀Ni-Cu-P合金,研究了镀液各组分浓度、pH值变化对沉积速度的影响.通过扫描电镜(SEM)观测镀层的表面形态及厚度,并用其所附带的能谱(EDS)分析镀层成分,采用透射电镜(TEM)观测镀层中粒子的微观形貌及大小,利用X-射线衍射(XRD)表征镀层的微观结构.结果表明,Ni-Cu-P合金化学镀层为非晶态合金,光亮、均匀,与基体结合面平整.镀层厚度100 μm,镀层颗粒大小在30～40 nm,各成分含量分别为77.73%～90.64% Ni,0.38%～5.27% Cu,7.23%～14.30% P.
关键词:
超声波
,
化学镀
,
Ni-Cu-P合金镀层
,
沉积速度
Physics Letters A
In a magnetic system, consistent with Griffiths analyticity requirements one can parameterize the equation of state near criticality by writing H = r(beta delta)h(theta), T = rt(theta) and the magnetization M = r(beta)m(theta), where T is measured from the critical temperature. For the insulating ferromagnet CrBr(3), the experimental data of Ho and Litster [J.T. Ho, J.D. Litster, Phys. Rev. Lett. 22 (1969) 6031 is well fitted by m(theta) as a linear function of theta [P. Schofield, J.D. Litster, J.T Ho, Phys. Rev. Lett. 23 (1969) 1098]. Also Ho and Litster give beta = 0.368, gamma = 1.215 and delta = 4.3. Those critical experiments are very close to the recent 31) king results of Zhang [Z.D. Zhang, Philos. Mag. 87 (2007) 5309], namely beta = 3/8, gamma = 5/4 and delta = 13/3. We therefore predict that m(theta) will be proportional to theta as a fingerprint of the 3D Ising Hamiltonian. (C) 2009 Elsevier B.V. All rights reserved.
关键词:
Critical-point effects;Critical exponents;Ising model;Criticality;Ferromagnet;Magnetic equation of state;critical exponents
Journal of Materials Research
The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.
关键词:
room-temperature
王雪俊
,
夏海平
材料导报
制备了χNb2O5-(10-χ)La2O3-60P2O5-10Na2O-19BaO-Eu2O3(以mol%记χ=9、7、5)的玻璃,测定了玻璃的吸收光谱、发射光谱、激发光谱、声子边带谱和差热分析曲线.从发射光谱出发获得了Eu3+光学跃迁的J-O参数Ω2、Ω4,并计算了Eu3+离子5DO→7FJ(J=1,2,4)的自发辐射跃迁几率A以及受激发射截面σp.结果显示,随着La2O3的增加和Nb2O5的减少,玻璃样品的热稳定性降低,强度参数Ω2减小,表明材料的对称性提高,共价性减弱,Eu-O键强减弱;随着La2O3的增加,电-声子偶合减弱,受激发射截面σp减小.
关键词:
光学材料
,
Eu3+离子掺杂铌镧玻璃
,
光谱性质
,
J-O理论
,
强度参数
,
受激发射截面
Materials Letters
The effects of P and B on the creep behavior of 718 alloys are discussed in this paper. The result implies that P and B have little effect on the gamma" and gamma' phases of the alloy, but they can enhance the grain boundary strength by segregating there, which can be of beneficial to the higher creep properties. P also may increase the grains strength through solid solution. The beneficial effect of P and B were presented in both standard IN718 alloy and DA718 alloy. Adding P and B together does a better work than adding P alone. (c) 2006 Elsevier B.V. All rights reserved.
关键词:
P and B;718 alloy;creep;grain boundaries;heat treatment;stress rupture;phosphorus;superalloy;boron
