H. Chen
,
X. Xin
,
D.Y. Dong
,
Y.P. Ren
,
S.M. Hao
金属学报(英文版)
The phase constitutes and phase compositions in the eight alloys designed with different compositions of Al-Zn-Cu system have been determined after the homogenous
treatment and then equilibrium cooling to 20±C by use of optical microscope, electron
probe microanalysis and X-ray di®raction. It has been found that there existed the T0
phase in the seven alloys. Consequently, it was testified that the T0 phase was stable
at room temperature. At the same time, the phase relationship was not locally right
for the isothermal section of 20±C of Al-Zn-Cu system of the ASM published in 1997.
关键词:
Al-Zn-Cu ternary system
,
null
,
null
,
null
常永勤
,
安卫军
,
郭喜平
,
介万奇
无机材料学报
采用Bridgman法生长了x为0.1,0.22和0.4的四元稀磁半导体化合物MnxCd1-xIn2Te4晶体.研究了三根晶体中相的形貌、结构、成分和Mn0.1Cd0.9In2Te4晶体中各组元沿轴向和径向的成分分布.晶体生长初始端的组织为α+β+β1,随着生长的进行,形成β相的单相区.在晶锭末端,形成In2Te3类面心立方结构化合物.组分x增大后,MnxCd1-xIn2Te4晶体的吸收边向短波方向移动,禁带宽度则线性增大.磁化率测量结果表明:晶体在高温区的x-1-T曲线服从居里-外斯定律,在低温区(<50K)则表现出顺磁增强现象.
关键词:
MnxCd1-xIn2Te4
,
compositional distribution
,
infrared transmission spectra
,
mag- netic susceptibility
常永勤
,
安卫军
,
郭喜平
,
介万奇
无机材料学报
doi:10.3321/j.issn:1000-324X.2003.02.004
采用Bridgman法生长了x为0.1,0.22和0.4的四元稀磁半导体化合物MnxCd1-xIn2Te4晶体.研究了三根晶体中相的形貌、结构、成分和Mno.1Cd0.9In2Te4晶体中各组元沿轴向和径向的成分分布.晶体生长初始端的组织为α+β+β1,随着生长的进行,形成β相的单相区.在晶锭末端,形成In2Te3类面心立方结构化合物.组分x增大后,MnxCd1-xIn2Te4晶体的吸收边向短波方向移动,禁带宽度则线性增大.磁化率测量结果表明:晶体在高温区的x-1-T曲线服从居里一外斯定律,在低温区(＜50K)则表现出顺磁增强现象.
关键词:
MnxCd1-xIn2Te4
,
成分偏析
,
红外透射光谱
,
磁化率
常永勤
,
介万奇
,
郭喜平
,
陈福义
,
安卫军
功能材料
研究了ACRT-B法生长的Mn0.1Cd0.9In2Te4晶体中界面的形状和各组元沿轴向的分布规律及其分凝因数.发现结晶界面为椭球形;采用理想配比生长MnxCd1-xIn2Te4晶体,其4种组元并不按(Mn,Cd):In:Te=1:2:4比例结晶,而是要重新分布;通过数学方法处理实验数据得到Mn,Cd和In的分凝因数在α相区分别为1.286、1.9257和0.7294,在β相区则分别为1.12、1.055和0.985.
关键词:
ACRT-B法
,
MnxCd1-x In2Te4
,
界面
,
分凝因数
常永勤
,
安卫军
,
郭喜平
,
介万奇
功能材料
采用Bridgman法生长四元稀磁化合物半导体Mn0.22Cd0.78In2Te4晶体.当晶体生长到预定长度时,淬火得到固液界面.采用光学显微镜、扫描电镜、X射线衍射仪、ISIS能谱仪以及Leica定量金相分析仪研究了晶体中出现的界面形态、相的形貌和数量以及沿生长方向的相析出规律,并进行了相成分分析.研究发现,淬火得到的Mn0.22 Cd0.78In2Te4晶体中存在两个界面,其中一个为固液相变界面,另一个为由α+β两相区发展到单相β区时的转变界面,二者相对于生长初始端均为凹形;α+β两相区中,β相以条状、花状和近似圆片状形式存在,其中条状β相多分布在晶界处;越接近生长初始端,花状和近似圆片状β相越小,条状β相越细,它们的含量越少;X射线衍射图谱表明,β相为黄铜矿结构,α相为面心立方结构.
关键词:
MnxCd1-xIn2Te4
,
相变界面
,
β相
,
X射线衍射图谱
Ieee Transactions on Magnetics
The microstructure, magnetic properties and magnetostriction of Tb0.2Pr0.8(Fe0.4Co0.6)(infinity) (1.65 less than or equal to x less than or equal to 1.90) alloys has been studied. The Curie temperatures for the 1:2 and 1:3 phases decrease with increasing x, whereas the saturation magnetization increases with increasing cc. The remanent magnetization remains almost constant for all the samples and the coercivity decreases with increasing x. The spontaneous magnetostriction (lambda (111)) estimated from the splitting of the (440) lines is found to decrease with increasing x. The largest lambda (111) recorded for Tb0.2Pr0.8(Fe0.4Co0.6)(1.65) is 2900 ppm at room temperature.
关键词:
Laves phase;microstructure;spontaneous magnetostriction;alloys
Y.M.Hao1) and Y.Gao2) 1)Department of Physics
,
Tianjin Normal University
,
Tianjin 300074
,
China 2)Library
,
Tianjin Normal University
,
Tianjin 300074
,
China
金属学报(英文版)
tructuraland magnetic propertiesof Ho2 AlFe16 x Mnx( x= 0 8) compoundshave been in vestigated by means of x ray diffraction and magnetization measurements. Thecompoundshave a hexagonal Th2 Ni17 typestructure. With increasing x,the unit cell volumes have a smallincreaseinitially,followed by a greaterlinearincrease. The Curietemperatureandthe saturation magnetization of these compounds show marvelous drop with increasing x. The valuesofJRTofthecompoundsfor x =2 ,3 , and 4 are given.
关键词:
unit cellvolume
,
null
,
null
,
null
Journal of Alloys and Compounds
Pseudo-1-3 magnetostrictive particulate composites consisting of light rare earth (Sm and Nd)-based magnetostrictive Sm(1-x)Nd(x)Fe(1.55) particles with the Nd content x of 0-0.56 and randomly distributed sizes of 10-180 mu m membedded and aligned in a passive epoxy matrix are fabricated using the particulate volume fraction of 0.5. The quasistatic magnetomechanical properties of the composites are investigated and the results are compared with their monolithic alloys for various x. The composites exhibit similar qualitative trends in properties with the alloys for all x. The Sm(0.92)Nd(0.08)Fe(1.55) composite shows a large unsaturated magnetostriction lambda of -530ppm at 500 kA/m and a high piezomagnetic coefficient d(33) of -2.0 nm/A at 100 kA/m as a result of the magnetocrystalline anisotropy compensation between Sm(3+) and Nd(3+) ions in the Sm(0.92)Nd(0.08)Fe(1.55) alloy. (C) 2011 Elsevier B.V. All rights reserved.
关键词:
Light rare earths;Magnetocrystalline anisotropy;Magnetomechanical;properties;Negative magnetostriction;Magnetostrictive composites;Sm(1-x)NdxFe(1.55) alloys;terfenol-d
Journal of Alloys and Compounds
Stabilizer (B, Co)-free, light rare earth (Pr)-substituted Laves alloys (Tb(0.3)Dy(0.7))(1-x)Pr(x)Fe(1.55) (0 <= x <= 0.4) are synthesized, and their structural, magnetic, and magnetostrictive properties are investigated. X-ray diffraction analysis confirms the presence of single cubic Laves phase with an MgCu(2)-type structure in the (Tb(0.3)Dy(0.7))(1-x)Pr(x)Fe(1.55) alloys with 0 <= x <= 0.35. The lattice parameter a of the Laves phase increases, while the Curie temperature decreases, with increasing x from 0 to 0.35. The saturation magnetization of the alloys decreases with increasing x. The linear anisotropic magnetostriction lambda(a) (=lambda(parallel to) - lambda(perpendicular to)) shows a maximum of 1502 ppm at x = 0.25 as a result of the magnetocrystalline anisotropy compensation. (C) 2008 Elsevier B.V. All rights reserved.
关键词:
Alloys and compounds;Laves phase;Light rare earths;Magnetocrystalline;anisotropy;Magnetostriction;Terfenol-D;anisotropy compensation;boron
Journal of Physics D-Applied Physics
Pseudo-1-3 magnetostrictive composites consisting of stabilizer ( B, Co)-free, light rare earth (Pr)-containing magnetostrictive (Tb(0.3)Dy(0.7))(1-x) Pr(x) Fe(1.55) (0 <= x <= 0.4) particles with a size distribution of 10-300 mu m embedded and aligned in a passive epoxy matrix using 0.5 volume fraction are fabricated. The quasistatic magnetomechanical properties of the composites are investigated and compared with their monolithic (Tb(0.3)Dy(0.7))(1-x) Pr(x) Fe(1.55) alloys, as a function of the Pr content x. The composites show similar qualitative trends in properties with the alloys for all x. The (Tb(0.3)Dy(0.7))(0.75)Pr(0.25)Fe(1.55) composite and alloy exhibit the smallest coercivity H(c), the largest magnetostriction lambda and the highest piezomagnetic coefficient d(33) due to the successful compensation for magnetocrystalline anisotropy. The ( Tb0.3Dy0.7) 0.75Pr0.25Fe1.55 composite demonstrates a large saturation magnetostriction lambda(s) of 793 ppm at 700 kAm(-1) and a high d(33) of 3.2 nmA(-1) at 140 kAm(-1). These values approach 81% and 85% of its alloy values at the same field levels. The good properties make the (Tb(0.3)Dy(0.7))(0.75)Pr(0.25)Fe(1.55) composite and alloy a promising magnetostrictive material system.
关键词:
terfenol-d;magnetic-properties;alloys;boron
