添加Zr的（Nd，Pr）10．5Fe81．5-xZrxCo286合金显微结构与磁性能

研究了添加Zr元素对快淬(Nd,Pr)10.5Fe81.5-xZrxCo2B6(x=0,0.5,1.0,1.5,2.0,2.5)合金显微组织结构和磁性能的影响,用AFM观察了合金条带自由表面的显微结构.结果表明添加Zr元素能显著细化合金的晶粒,从(Nd,Pr)10 5Fe81 5Co2B6合金的～150 nm减小到(Nd,Pr)10.5Fe80Zr1.5Co2B6合金的～50 nm;1%是Zr最佳添加量,低于1%晶粒不够细化,合金的各项磁性能指标均很低,超过1%,富集在晶界处的富Zr晶间相加厚,晶粒间的交换作用和剩磁增强效应减弱,磁体的剩磁Br和最大磁能积(BH)m降低.(Nd,Pr)10.5Fe80.5Zr1Co2B6粘结磁体磁性能最佳Br=0.675 T,Hci=616 kA·m-1,(BH)m=77 kJ·m-3.     

Dy元素对纳米复合(Nd,Pr)_(10.5-x)Dy_xFe_(83.5)B_6合金磁性能与显微结构的影响（英文）EI北大核心CSCD

采用快淬法制备了镨基(Nd,Pr)10.5-x Dyx Fe83.5B6(x=0.0,0.5,1.0,1.5,2.0,2.5)系列粘结磁体,研究了Dy元素添加对快淬合金显微组织结构、磁性能及快淬薄带热稳定性的影响。与Nd2Fe14B相比,硬磁相Dy2Fe14B具有较高的磁晶各向异性场HA和较低的饱和磁极化强度Js,因此,Dy元素添加能显著提高合金的内禀矫顽力Hcj,但会降低合金的剩磁Br。Dy元素替代Nd/Pr元素,增强了快淬薄带的热稳定性,提高了晶化退火温度。较高的晶化退火温度,使快淬薄带中已经形成的微晶更容易长大,形成一些粗大晶粒,降低了粘结磁体的磁性能。1.0%是较佳的Dy元素添加量,(Nd,Pr)9.5Dy1Fe83.5B6合金快淬粘结磁体的最大磁能积(BH)max为71.6 k J/m3,剩磁Br为0.638 T,内禀矫顽力Hcj为611 k A/m。     

Dy元素对纳米复合(Nd,Pr)_(10.5-x)Dy_xFe_(83.5)B_6合金磁性能与显微结构的影响（英文）

采用快淬法制备了镨基(Nd,Pr)10.5-x Dyx Fe83.5B6(x=0.0,0.5,1.0,1.5,2.0,2.5)系列粘结磁体,研究了Dy元素添加对快淬合金显微组织结构、磁性能及快淬薄带热稳定性的影响。与Nd2Fe14B相比,硬磁相Dy2Fe14B具有较高的磁晶各向异性场HA和较低的饱和磁极化强度Js,因此,Dy元素添加能显著提高合金的内禀矫顽力Hcj,但会降低合金的剩磁Br。Dy元素替代Nd/Pr元素,增强了快淬薄带的热稳定性,提高了晶化退火温度。较高的晶化退火温度,使快淬薄带中已经形成的微晶更容易长大,形成一些粗大晶粒,降低了粘结磁体的磁性能。1.0%是较佳的Dy元素添加量,(Nd,Pr)9.5Dy1Fe83.5B6合金快淬粘结磁体的最大磁能积(BH)max为71.6 k J/m3,剩磁Br为0.638 T,内禀矫顽力Hcj为611 k A/m。     

双相纳米晶Nd10Fe75Co5Zr3Cr0．5B6．5磁体的研究

采用熔体快淬及晶化热处理工艺制备Nd10Fe75Co5Zr3Cr0.5B6 5纳米晶合金.快淬薄片(17m·s-1)在710℃,4 min晶化处理后,晶粒尺寸为50 nm～60 nm.该快淬薄片经710℃,4min晶化处理后制成的粘结磁体的磁性能为Br=0.67 T,JHc=707 kA·m-1和(BH)max=74 kJ·m-3.     

纳米晶Nd10.1Fe76.2Co4.5Zr3B6.2 永磁材料制备工艺和磁性能的研究

采用熔体快淬及热处理工艺制备Nd10.1Fe76.2Co4.5Zr3B6.2永磁材料,研究了制备工艺参数和热处理工艺对材料结构和磁性能的影响.结果表明,粘结磁体的磁性能与熔体快淬和热处理工艺密切相关,快淬速度为20m/s的薄带经690℃×4min退火处理可得到最佳磁性能Br=0.714T、JHc=698kA/m、(BH)max=82.0kJ/m3.     

Influence of zirconium addition on the microstructure and magnetic properties of nanocomposite Nd10.1Fe78.2-xCo5ZrxB6.7 permanent magnets

Nanocomposite Nd10.1Fe78.2-xCo5ZrxB6.7 （x= 0, 1.5, 2.5, 2.7, 3, 4） permanent magnets were prepared by melt-spun and annealing. The microstructure and magnetic properties of the permanent magnets were investigated. The resuits reveal that the addition of Zr element significantly reduces the grain size and improves the thermal stability of the amorphous phase. A fme nanocomposite microstructure with an average grain size of about 35 nm can be developed at a wheel speed of 16 m·s^-1 with the content of Zr up to 2.7 at.%. After optimal annealing （710℃ x 4 min）, the magnetic properties of the Ndl0.1Fe75.5Co5Zr2.TB6.7 bonded magnets were achieved as follows： Br= 0.72 T, jHc = 769 kA·m^-1, and （BH）max = 85.0 kJ·m^-3.     

Nd_x(Fe_(0.933)B_(0.067))100-x纳米合金的磁性

台湾清华大学研究了Ndx(Fe0.933B0.067)100-x合金的磁性．将合金成分Fe／B比率固定在14，变化Nd含量、试验合金Ndx(Fe0.933B0.067)100-x（x=3，4，5，6，8和11）用单辊快淬法制备，辊速40fn／s，M气保护．热处理采用加热速度大于600℃／min的快速退火工艺．实验结果表明，热处理后Ndx(Fe0.933B0.067)100-x内禀矫顽力从X=3的27.2hA／m升到X=11的725．6bA/m，剩磁风从x=3的1．44gT降到x=11的1．04Th，科磁比在0．71～0．78及最大磁能积(BH)max为150.4kJ/m3．平均形核场从：x=3时80kA／m，x—4.5时200hA／m,x—6时320hA／m，x—8时40…     

Dy元素对快淬(Nd, Pr)FeB合金的磁性能和晶化转变温度的影响

采用快淬法制备了镨基(Nd,Pr)10.5-xDyxFe83.5B6 (x=0,1,2)系列粘结磁体,测定了快淬条带晶化转变温度,研究了添加Dy元素对快淬合金条带晶化转变温度的影响。合金中添加Dy元素,快淬态条带晶化过程中非晶态向晶态转变的开始温度及结束温度提高,转变的温度区间增大。由于热稳定性的提高,条带晶化退火需要采用较高的温度。添加2%Dy元素的(Nd,Pr)8.5Dy2Fe83.5B6合金,最佳退火温度比 (Nd,Pr)9.5Dy1Fe83.5B6和(Nd,Pr)10.5Fe83.5B6分别提高了15和30 ℃。添加Dy元素的粘结磁体,内禀矫顽力Hcj增加,但剩磁Br下降,实验制备的(Nd,Pr)9.5Dy1Fe83.5B6合金磁体的磁性能为Br=0.638 T,Hcj=611 kA/m,(BH)m=71.6 kJ/m3     

Cu对纳米晶复合合金Nd_(9.5)Fe_(76-x)Cu_xCo_5Zr_3B_(6.5)(x=0～2)磁性能的影响

采用快淬后真空晶化处理的方法制备出纳米晶复合合金Nd9.5Fe76-xCo5Zr3CuxB6.5(x=0～2),系统地研究了Cu元素对其磁性能的影响。结果表明:适量Cu元素的添加,可以提高磁体的剩磁Br、内禀矫顽力jHc和最大磁能积(BH)max,并且可以有效地提高磁体的剩磁温度系数α,但使磁体的矫顽力温度系数β略有降低。当Cu含量为0.25 at%时,该磁体具有最佳的综合磁性能:(BH)max=79 kJ/m3,jHc=685 kA/m,Br(T)=0.713 T;剩磁温度系数α20～150℃=0.071%/℃;矫顽力温度系数β20～150℃=0.36%/℃。     

(Fe_(1-x)Co_x)_(80)Zr_(10)B_(10)(x=0,0.1,0.2,0.3)合金的热性能、结构和磁性能研究

采用单辊快淬法制备(Fe1-x Cox)80Zr10B10(x=0,0.1,0.2,0.3)非晶合金,并对4种合金在不同温度下进行等温热处理。利用差热分析仪(DTA),X射线衍射仪(XRD),透射电镜(TEM)和振动样品磁强计(VSM)等测试手段对样品的热性能、微观结构及磁性能进行研究。结果表明,未添加Co元素的Fe80Zr10B10合金的热稳定性明显高于添加Co元素的合金,而(Fe1-x Cox)80Zr10B10(x=0.1,0.2,0.3)合金的热稳定性相差不大。Fe80Zr10B10和Fe72Co8Zr10B10合金的晶化过程相似;Fe64Co16Zr10B10和Fe56Co24Zr10B10合金的晶化过程相似。4种合金的矫顽力(Hc)呈现先上升后下降的趋势,在873 K达到最大值。     

Polarographic behavior of 1,4,7-triazacycloanane-N,N'''',N"-tris (meth-ylphonic acid) (NOTP)-Bi(Ⅲ) complex

The polargraphic behavior of Bi(III)-NOTP complex has been investigated in aqueous solution. It was found thatunder the conditions of pH 3.0 and of 0.02 mol/L NH4Cl, the Bi(III)-NOTP system gives a sensitive second order derivativewave at -0.340 V(vs SCE), which is proved to be an adsorptive complex wave. The composition of the complex isBi(III):NOTP. Furthermore, the peak current is linear to the concentration of Bi(III) in the range from 3.0×10-8 to 5.0×10-6mol/L. Artificial and practical samples have been detected with high sensitivity and receptivity.     

Fe_(0.85)Mn_(0.15)Ti_(0.9)M_(0.1)(M=Zr,V,Ca)合金的贮氢性能

系统地研究了 Fe0 .85 Mn0 .1 5 Ti0 .9M0 .1 (M=Zr,V,Ca)合金的贮氢性能。研究结果表明 :Fe0 .85 Mn0 .1 5 Ti0 .9Zr0 .1 合金在室温下经几分钟的孕育期就可吸氢 ,但合金在氢化过程中形成了氢含量很高的α相 ,导致合金的贮氢量降低 ,同时还使 p- c- T曲线的平台特性变差 ;Fe0 .85 Mn0 .1 5 Ti0 .9V0 .1 合金的活化性能进一步得到改善 ,在室温下几乎不需要孕育期就可以吸氢 ,但同时要降低合金的贮氢量 ,而对合金的 p- c- T曲线平台特性影响不明显 ;用 Ca取代 Fe0 .85 Mn0 .1 5 Ti合金中的部分 Ti则对合金的贮氢性能影响不明显。通过 XRD分析认为 ,上述性能的变化主要与合金中出现第二相有关     

新型复合贮氢合金Zr_(0.9)Ti_(0.1)(Ni,Co,Mn,V)_(2.1)的制备与电化学性能

采用熔铸方法制备母合金Zr0 .9Ti0 .1(Ni,Co ,Mn ,V) 2 .1,进而在母合金基础上添加吸氢剂B ,利用球磨制得 4种复合贮氢合金。X射线衍射结果表明 ,随着球磨时间的增加 ,复合合金由晶态转化为非晶态 ;电化学测试结果表明 ,复合合金经过 1～ 2次球磨就能完全活化 ,具有很好的活化性能 ;在 6 0mA/g电流下 ,复合贮氢合金C和D的稳定容量均可达到 44 0mA·h/ g左右 ,比母合金高出 80mA·h/ g ;但随着球磨时间的延长 ,所得的复合合金容量比铸态母合金的还低 ;在 30 0mA/g电流下 ,复合合金D具有较好的循环稳定性 ,经过 2 0 0次循环后其容量仅衰减 3 %。     

LaDy_(0.1)Fe_(11.4)T_(0.1)Si_(1.5)(T=Mn,Fe,Co)合金的磁热效应

使用电弧炉熔炼制备了LaDy0.1Fe11.4T0.1Si1.5(T=Mn,Fe,Co)系列合金。XRD分析表明该系列合金具有NaZn13型立方单相晶体结构,空间群为Fm-3c。磁性测量表明:随着替代原子T原子半径的减小,合金的居里温度(TC)逐渐增大。在外场变化ΔB=1.5T时,该系列合金的最大磁熵变分别为12.3,25.0,11.4J/kg·K。     

CRYSTALLIZATION KINETICS OF Pd(Fe,Co,Ni)_(0.05-0.15)Si_(0.17) METALLIC GLASSES

用测量等温退火过程中试样的电阻变化对Pd(Fe,Co,Ni)_(0.05-0.15)Si_(0.17)金属玻璃的结晶动力学进行了研究。在等温退火过程中,试样的电阻下降一般为10—20％,Pd-Fe-Si系试样的电阻变化直接与含Fe量有关,Pd_(0.78)Fe_(0.05)Si_(0.17)在等温结晶中电阻反而升高。从动力学观点看,在Pd-Si系中添加Fe,Co和Ni使结晶活化能增加,结晶模式指数减小,从而使金属玻璃变得稳定。衡量金属玻璃的稳定性要同时考虑其热力学稳定性和动力学稳定性。     

(Fe,Cu,Nb)_(77.5)Si_xB_(22.5-x)纳米晶合金的结构和磁性研究

研究了Ｆｅ_（７４．５）Ｃｕ_１Ｎｂ_２Ｓｉ_ｘＢ_（２２．５－ｘ）纳米晶合金中Ｓｉ（Ｂ）含量的变化（ｘ＝９．５－１７．５）对其结构和磁性的影响．结果表明，随着ｘ的增高，合金的Ｃｕｒｉｅ温度及点阵常数皆呈线性下降．由此推定α－Ｆｅ（Ｓｉ）纳米晶粒中的Ｓｉ含量ｘ_α随ｘ增高而线性升高，并符合下列关系ｘα＝０．６２６ｘ＋１０．５实验结果说明，非晶态合金的λｓ值随ｘ的增加而上升，但晶化后合金的λｓ值随ｘ的增加而降低．在一定温度退火后的合金中，纳米晶的体积百分数Ｖｘ随ｘ的增大而增加．     

Synthesis,characterization,and thermostability of bis(2,2,6,6-tetramethyl-3,5-heptanedionato)copper(Ⅱ)

Owing to the adaptability to large scale processing,excellent composition control and film uniformity,the metal-organic chemical vapor deposition(MOCVD)technique is a promising process for high-temperature superconductor YBa2Cu3O7-δ(YBCO)preparation.In this technique,the evaporation characteristics and thermostability of adopted precursors in whole process will decide the quality and reproducible results of YBCO film.In the present report,bis(2,2,6,6-tetramethyl-3,5-heptanedionato)copper(Ⅱ)(Cu(TMHD)2)was synthesized by the interaction of copper acetate hydrate with TMHD in methanol solution,and its structure was identified by FTIR,1H NMR,and EI-MS spectroscopy.Subsequently,thermal property and the kinetics of decomposition were systematically investigated by nonisothermal thermogravimetric analysis methods(TGA)at different heating rates in streams of N2,and the average apparent activation energy of evaporation process was evaluated by the Ozawa,Kissinger,and Friedman methods.The possible conversion function was estimated through the Coats-Redfern method to characterize the evaporation patterns and followed a phase boundary reaction mechanism by the contracting area equation with average activation energy of 85.1 kJ·mol-1.     

Enthalpies of Formation of (Cu,Ni)3Sn, (Cu,Ni)6Sn5-HT and (Ni,Cu)3Sn2-HT

Standard enthalpies of formation of ternary phases in the Cu-Ni-Sn system were determined along sections at 25, 41 and 45.5 at.% Sn applying tin solution drop calorimetry. Generally, the interaction of Ni with Sn is much stronger than that of Cu with Sn. Along all sections the enthalpy of formation changes almost linearly with the mutual substitution of Cu and Ni within the respective homogeneity ranges. Thus no additional ternary interaction promoting the formation of further Cu-Ni-Sn phases can be assumed. The results are discussed and compared with literature values relevant to this system.     

Site Preferences of Pr and Co in(Nd,Pr)_2(Fe,Co)_(14)B Compounds

The Curie temperature of(Nd_(1-x)Pr_x)_2Fe_(14)Co_yB compounds(x=0,0.2,…,1.0 and y=O,2,4,6,14)hasbeen determined with AC initial susceptibility measurement.It was found that the variations of Curie tempera-ture with x is not linear for y=0 and 14,whereas it is linear for other values of y.The lattice constants of(Nd_(1-x)Pr_x)_2Fet_(14)B were determined by using X-ray diffraction.The lattice expansion was mostly along the caxis,whereas that along the a-axis remained practically zero for the whole series.It is suggested that Pr atomsmay show site preference in R_2M_(14)B compounds(M=Fe or Co).Due to the substitution of Co for Fe.thetendency of site preference of Pr becomes less pronounced,which may be attributed to the decrease of differ-ence of crystal electric field(CEF)acting on the two rare earth sites with the introduction of Co or Fe.In con-trast to that of the Pr atoms,the site preference of Co iu(Nd(1-x)Pr_x)_2Fe(14-y)Co_yB compounds does not depend onthe composition of the rare earth sublattice(R=N d or Pr).