Y.Chen X.Chen A.M.Guo D.X.Luo
,
B.F.Xu
,
Z.X.Yuan
,
P.H.Li
,
S.K.Pu
,
S.B.Zhou
金属学报(英文版)
The different chemical composition of silicon and manganese as well as different re-tained austenite fraction ranged from 4to 101163326174f the high strength and high elon-gation steels were studied in the paper.The dislocations and carbon concentration in retained austenite were observed by a transmission electron microscope and an electric probe analyzer,respectively.The experimental results showed that silicon and manganese are two fundamental alloying elements to stabilize austenite effectively but retaining austenite in different mechanis-↑ms.Meanwhile,the cooling processing played an important role in controlling the fraction of retained austenite of the hot-rolled high strength and high plasticity steels.
关键词:
high strength
,
null
,
null
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
李开明
,
李亚洲
,
冯维贵
,
林长
量子电子学报
doi:10.3969/j.issn.1007-5461.2007.05.014
采用非线性反馈控制,用附加了带参数的正弦项对Chen系统进行了有效的控制.随着参数k的逐渐增大,系统的动力学行为呈现出一系列的变化.数值研究结果表明:随控制参数的增大,驱动信号的强度渐大,混沌系统由混沌运动到周期轨道,最终到一相点.
关键词:
混沌
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Chen系统
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不动点
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Lyapunov指数
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反馈控制
王龙章
,
黄克雄
,
骆如铁
,
姚渝
,
叶大陆
,
陈新民
金属学报
本文讨论了双金属共存体系M_1-M_2-x-y,当两种金属的化合物相互作用生成多金属化合物时,优势区相图的绘制原理、方法及计算机程序。通过绘制Zn-Fe-SO系的优势区相图,分析了ZnO·Fe_2O_3的生成及稳定条件,并说明了其在硫化锌矿焙烧中的指导作用。
关键词:
M_1-M_2-x-y体系
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predominance diagram
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roasting
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zinc sulfide ore
Applied Physics Letters
The effect of nonmagnetic Y partial substitution at the Dy site in Dy(1-x)Y(x)MnO(3) up to x=0.2 on magnetism, specific heat, and ferroelectricity is investigated, which resulted in a preliminary multiferroic phase diagram. It is revealed that the Y partial substitution suppresses the Dy-spin ordering point (T(Dy)) and ferroelectric ordering point (T(FE)) but enhances the Mn-spin ordering point (T(N)). The interaction between the spins of Dy and Mn is remarkably affected by Y substitution. The measured electrical polarization depends on the Y substitution in a complex way because the ferroelectricity is sensitive to the interaction between the spins of Dy and Mn. (c) 2011 American Institute of Physics. [doi: 10.1063/1.3536506]
关键词:
ferroelectricity;polarization
张志纯
,
龙志林
,
危洪清
,
李乡安
,
彭建
,
唐平
稀有金属材料与工程
采用单辊法和铜模铸造法制备了Fe75-xMxHf3Y2B20(M=Co,Nb;x=0,4 at%)合金系的非晶薄带和非晶棒样品,并测试了该非晶合金系的差示扫描量热曲线、X射线衍射图谱和软磁性能.结果表明:少量的Nb或Co替代Fe75Hf3Y2B20中的Fe元素,合金的热稳定性和玻璃形成能力可得到明显的提高;其中Fe71Nb4Hf3Y2820的过冷液相区宽度△Tx高达75 K,约化玻璃转变温度Trg为0.58,直径达4 mm,饱和磁感应强度为0.97～1.08 T,该非晶合金同时具有较大的热稳定性、较强的玻璃形成能力和较好的软磁性能.
关键词:
铁基块体非晶合金
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过冷液相区
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玻璃形成能力
,
软磁性能
材料科学技术（英文）
The glass-forming ability (GFA) of Nd(70-x)Fe(20)Al(10)Y(x) and Nd(60-x)Fe30Al(10)Y(x) (0 less than or equal to x less than or equal to15) alloys produced by Cu mold casting was investigated. Except Y = 5 at. pct, bulk amorphous Nd(70-x)Fe(20)Al(10)Y(x) alloys up to 2 mm in diameter were obtained. The GFA for Nd(60-x)Fe(30)Al(10)Y(x) alloys, however, was found to decrease with increase of Y due to the increasing compositional deviation from the original eutectic point of Nd(60)Fe(30)Al(10) alloy. The Nd(60)Fe(20)Al(10)Y(10) and Nd(60)Fe(30)Al(10) alloy exhibit the largest GFA and can be cast into bulk amorphous cylindrical specimens of 3 mm in diameter. The melting temperature or/and the reduced crystallization temperature is closely related to the GFA of Y-containing alloys. The bulk amorphous cylinder for the Nd(55)Fe(20)Al(10)Y(15) alloy shows a distinct glass transition temperature and a wide supercooled liquid region before crystallization. The crystallization temperature, T(g), and the supercooled liquid region, DeltaT(x), are 776 K and 58 K, respectively, The GFA and thermal stability of the Nd-Fe-Al-Y alloys were discussed.
关键词:
Nd-based alloys;glass forming ability;liquidus temperature;thermal;stability;supercooled liquid region;bulk amorphous-alloys;metallic glasses;transition temperature;thermal-stability;atomic size;ni alloys;cu;alloys;diameter;tm
Physica B-Condensed Matter
The magnetic properties and magnetocaloric effect of Tb(1-x)Y(x)CoC(2) (x = 0, 0.1, 0.2, 0.3, 0.4) compounds have been investigated systematically. All the compounds undergo second-order transitions from paramagnetic to ferromagnetic states without thermal and magnetic hysteresis. With increasing Y content from 0 to 0.4, the Curie temperatures decrease nearly linearly from 28 to 18 K. The nature of the second-order phase transitions can be confirmed by Arrott plots. For Tb(0.6)Y(0.4)CoC(2) compound, the maximum value of the magnetic entropy change -Delta S(M) at 20 K is 9.35 J kg(-1) K(-1) for an external field change of 5T (5.14 J kg(-1) K(-1) for 2T). The large reversible magnetic entropy change makes Tb(0.6)Y(04)CoC(2) compound an attractive candidate for the application at hydrogen liquefaction temperature. (C) 2010 Elsevier B.V. All rights reserved.
关键词:
Curie temperature;Magnetocaloric effect;Magnetic properties;ac susceptibility
门德
,
松林
,
伊博乐
,
刘璟芳
,
伊日勒图
,
特古斯
稀有金属
doi:10.3969/j.issn.0258-7076.2010.01.027
研究了1:1型MnP基系列合金MnP_(1-x)M_x(M=Si,Sb,Ge,Zn,Sn)(x=0,0.1)的结构及其磁热效应.室温X射线衍射表明该系列合金的主相结构均为正交MnP结构,空间群为Pnma.在用Ce,Sb,Zn,Sn作为替代元素的合金中存在少量第二相Mn_(5.64) P_3.磁性测量表明该系列合金MnP_(1-x)M_x(M=Si,Sb,Ge,Zn,Sn)(x=0,0.1)的存在由铁磁-顺磁的二级相变.其居里温度T_c分别为286,295,291,295,295 K.通过磁化曲线计算了MnP_(1-x)M_x(M=Si,Sb,Ge,Zn,Sn)(x=0,0.1)合金的最大等温磁熵变-△S_m,均在0.7-1.3 J·kg~(-1)·K~(-1)之间.
关键词:
合金
,
磁制冷
,
磁热效应
,
磁熵变
