Glass-Forming Ability for Nd_(70-x)Fe_(20)Al_(10)Y_x and Nd_(60-x)Fe_(30)Al_(10)Y_x Alloys

The glass-forming ability (GFA) of Nd70-xFe2oAl10Yx and Nd60-xFe30Al10Yx (0< x <15) alloys produced by Cu mold casting was investigated. Except Y=5 at. pct, bulk amorphous Nd70-xFe20Al10Yx alloys up to 2 mm in diameter were obtained. The GFA for Nd60-xFe30Al10Yx alloys, however, was found to decrease with increase of Y due to the increasing compositional deviation from the original eutectic point of Nd60Fe30Al10 alloy. The Nd60Fe20Al10Y10 and Nd60Fe30Al10 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 Nd55Fe20Al10Y15 alloy shows a distinct glass transition temperature and a wide supercooled liquid region before crystallization. The crystallization temperature, Tg, and the supercooled liquid region, TX, are 776 K and 58 K, respectively. The GFA and thermal stability of the Nd-Fe-AI-Y a     

Fe61Co10Zr5W4B20块体非晶合金的形成及其力学性能

采用铜模吸铸法获得直径为2 mm的Fe61Co10Zr5W4B20块体非晶合金.采用X射线衍射、扫描电镜、示差扫描量热仪、微显硬度及压缩实验等研究了非晶合金的结构、热稳定性、显微硬度与压缩性能.结果表明:Mo的引入不利于非晶合金的形成;Fe61Co10Zr5W4B20块体非晶合金表现为二级晶化,玻璃转变温度为561.1℃,晶化起始温度为619.0℃,第一晶化峰值温度为632.6℃,第二晶化峰值温度为747.0℃,过冷液相区为57.9℃;该非晶合金的显微硬度为1207HV0.2,抗压强度σbc为1707.6 MPa.     

添加AlN对机械合金化Zr65Al7.5CU17.5Ni10非晶态合金热稳定性的影响

以成分为Zr65Al7.5Cu17.5Ni10的元素的粉末混合物及AIN颗粒为起始材料,经机械合金化形成非晶态合金为基体的复合材料,AIN添加量为5％－30％（体积分数,下同）,利用X射线衍射（XRD）,透射电子 显微镜（TEM）和差示扫描量热计（DSC）分析了含AIN复合材料的结构特性,玻璃转变与晶化行为,TEM观察表明,AIN第二相粒子弥散分布在晶Zr基合金基体上,粒子尺寸为20－200nm,仍为初始的晶体结构,与未添加AIN的Zr基非晶态合金相比,含5％－10％AIN的复合材料仍表现出较宽的过冷液态温度区域,玻璃转变温度（Tg)和晶化激活能（Ex)没有显著变化,但晶化起始温度（Tx)向高温移动大约10K,导致过冷液态温度区域的扩宽,AIN含量增至30％,明显的玻璃转变消失,Tx升高的20K。     

大块非晶合金Zr55Cu30Al10Ni5的电子结构特征及电击穿行为

测定了大块非晶合金Zr55Cu30Al10Ni5晶化前后的费米能级和各元素的电子结合能，研究了非品合金的电子结构特征和电击穿行为．测试并讨论了非晶材料场发射能力和耐电压强度的关系．结果表明，对于Zr基合金，非品态比品态合金具有更大的功函数．比较了Zr55Cu30Al10Ni5合金非晶态与晶态的耐电压强度数值，发现非晶态合金的耐电压强度数值比较分散，品化合金的耐电压强度相对比较集中．耐电压强度平均值表明，Zr基合金非晶态具有更好的耐电压能力．     

Glass Formability and Soft Magnetic Properties of Bulk Y-Fe-B-Ti Metals

The Ti effects on the glass forming ability and the magnetic properties of Y-Fe-B-Ti bulk metallic glasses have been investigated. Substituting 2 and 4 at% Ti for Fe or B in Y6 Fe20 B22 alloys decrease the saturation magnetization （a,） and deteriorate the glass forming ability, respectively. However, substitution of 2 at% Ti for Y in Y6 Fe72 B22 alloy induces larger supercooled region of 72.7 ℃ , which not only makes the bulk glassy rod as large as 3mm in diameter, coercivity （ Hc ） = 0.20e and Curie temperature （Tc） = 268℃ . glass forming ability and also the proper soft magnetic properties. but also results in the superior soft magnetic properties of a, = 126emu/g, Among all Y-Fe-B-Ti bulk amorphous rods, Y4Fe72B22Ti2 displays the best     

High formability of glass plus fcc-Al phases in rapidly solidified Al-based multicomponent alloy

A multicomponent Al₈₄Y₉Ni₄Co_1.5Fe_0.5Pd₁ alloy was found to keep a mixed glassy + Al phases in the relatively large ribbon thickness range up to about 200 μm for the melt-spun ribbon and in the diameter range up to about 1100 μm for the wedge-shaped cone rod prepared by injection copper mold casting. The glassy phase in the Al-based alloy has a unique crystallization process of glass transition, followed by supercooled liquid region, fcc-Al + glass, and then Al + Al₃Y + Al₉ (Co, Fe)₂ + unknown phase. It is also noticed that the primary precipitation phase from supercooled liquid is composed of an Al phase instead of coexistent Al + compound phases, being different from the crystallization mode from supercooled liquid for ordinary Al-based glassy alloys. In addition, it is noticed that the mixed Al and glassy phases are extended in a wide heating temperature range of 588–703 K, which is favorable for the development of high-strength nanostructure Al-based bulk alloys obtained by warm extrusion of mixed Al + amorphous phases. The Vickers hardness is about 415 for the glassy phase and increases significantly to about 580 for the mixed Al and glassy phases. The knowledge of forming Al + glassy phases with high hardness in the wide solidification and annealing conditions through high stability up to complete crystallization for the multicomponent alloy is promising for future development of a high-strength Al-based bulk alloy.     

非晶态合金条带高压复合法制备大块非晶态合金

介绍一种制备大块非晶态合金的新方法－快淬非晶态合金和条带高压复合法，其原理是利用高压抑制非晶态合金的晶化过程，从而在较宽的温区通过大量均匀的粘滞流变实现快淬非晶态合金条带的全致密复合。     

Ni,Fe对Al90TM5Ce5非晶合金稳定性的影响

本文研究了Al90 Fe5Ce5和A190 Ni5Ce5非晶合金及预峰在晶化过程和时效过程中的稳定性。Al90Fe5Ce5非晶合金的晶化开始温度TX 和时效稳定性比Al90 Ni5Ce5非晶合金高。Al90 Fe5Ce5非晶合金预峰所对应的化学短程序结构的稳定性较高 ,而Al90 Ni5Ce5非晶合金预峰所对应的化学短程序结构的稳定性差 ,甚至通过常温时效消失。非晶合金的稳定性与预峰所对应的化学短程序结构的稳定性有密切关系     

铁钴镍基非晶态软磁材料的研究

研究了１０钟以铁钴镍为基的非昌态软磁材料，对非晶态合金的成分，熔点，晶化温度，居里温度及一些磁性能作了分析比较、将将材料制成元件装到电子镇流器上试验，研究结果表明，铁磁元素铁钴镍的含量比例，是影响非晶态磁性的主要因素；类金属元素对软磁材料的磁性能也有一定的影响，含磷的非晶态合金的熔点，晶化温度及居里温度比含碳的较高。     

Investigation of Micro Formability of Bulk Amorphous Alloy in the Supercooled Liquid State Based on Fluid Flow and Finite Element Analysis

Research results on the viscous flow deformation behavior of bulk amorphous alloy in different systems are reviewed. The material exhibits an ideal Newtonian fluid at a high temperature. Analytical solution of lamellar fluid flow behavior is used to discuss the viscous flow behavior of the bulk amorphous alloy in the supercooled liquid state. A material model, which describes such deformation behavior of Mg60Cu30Y10 amorphous alloy,is introduced into the finite element method of microforming process. Surface feature size was investigated and found not sensitive to the micro formability. Bulk amorphous alloy may possibly be applied to microelectro-mechanical-systems (MEMS) fabrication.     

Nd58Fe20Al10Co10B2大块非晶合金磁性能的研究

利用示羔扫描量热法，X射线衍射法、振动样品磁强计和扫描电镜研究了热处理对硬磁性非晶合金Nd58Fe20Al10Co10B2磁学性能的影响。研究表明，随着热处理温度的升高，非晶基体中的团簇的数量不断减少以及晶化过程中析出的晶体相或亚稳相对磁畴的钉扎作用的破坏，使矫顽力、剩余磁化强度、饱和磁化强度都逐渐降低。大量晶化后，Nd-Fe、Nd—Fe-(Al、Co)团簇之间耦合作用的消失是硬磁性消失的主要原因。     

Ferromagnetic Fe-based Amorphous Alloy with High Glass-forming Ability

A ferromagnetic amorphous Fe73Al4Ge2Nb1P10C6B4 alloy with high glass-forming ability was synthesized by melt spinning. The supercooled liquid region before crystallization reaches about 65.7 K. The crystallized structure consists of alpha -Fe, Fe3B, FeB, Fe3P and Fe3C phases. The Fe-based amorphous alloy exhibits good magnetic properties with a high saturation magnetization and a low saturated magnetostriction. The crystallization leads to an obvious decrease in the soft magnetic properties.     

Fe45Co7Cr15Mo10Y2B6C15大块非晶合金的晶化动力学研究

为了明确Fe基块体非晶材料的晶化过程,通过铜模吸铸法制备了Fe45Co7Cr15Mo10Y2B6C15块体非晶合金,采用连续和等温差热扫描量热法对非晶合金在1 000 K以下的晶化动力过程进行了研究.研究表明:在973 K时效后的晶化产物为铁的碳化物;晶化过程的激活能达到了555.9 kJ/mol,非晶热稳定性良好;Avrami常数n值接近2,随着退火温度的变化,n值没有明显的变化,非晶晶化机理没有发生改变,而放热峰宽随着退火温度的降低明显宽化,说明非晶晶化过程是一个二维扩散控制的形核与长大过程.     

弛豫对Zr-Al-Ni-Cu基非晶合金晶化过程的影响

非晶合金的稳定性是制备大块非晶合金的关键，而弛豫后形成的短程有序结构对非晶中的晶体相形核有重要的影响。本文通过差热分析及X射线衍射法研究了预先弛豫处理对Zr60Al8Ni12.5Cu17Si2.5和Zr60Al8Ni10Cu17Si5非晶合金晶化过程的影响。结果表明：预先弛豫处理降低了上述非晶合金的稳定性。Si含量的增加则提高上述非晶合金的稳定性。根据等温转变过程日体相形核孕育期采用Arrhenius公式所确定的晶化激活能更能反映非晶晶化过程及非晶的稳定性。     

Pressure Effect on Crystallization of Zr55Cu30Al10Ni5 Bulk Metallic Glass

The effect of pressure on the variation of the crystallization phases of the Zr55u30Al10Ni5 bulk glass and its thermal stability under high pressure annealing was investigated by X-ray diffraction (XRD)and differential scanning calorimeter(DSC).The mode of crystallization and products of crystallization of the Zr55Cu30Al10Ni5 bulk glass were quite different pressure.At ambient pressure,the crystallization products consisted of NiZr2 and CuZr2,while at pressure of 1 Gpa and 3 Gpa,the alloys crystallized into NiZr2 and Cu10Zr7,respectively.The alloy was nearly not crystallized and only a small amount of Cu10Zr7 was precipitated under 5 Gpa.DSC proved that the mode of the crystallization under high pressure was different from that at ambient pressure.     

Impurity-driven nanocrystallization of Zr-based bulk amorphous alloys

The effect of oxygen content and Ti addition on the glass forming ability (GFA) and crystallization kinetic of Zr-based bulk glass forming alloys have been studied by means of thermal analysis and X-ray diffraction techniques. Presence of oxygen triggers the formation of a nanocrystalline metastable f.c.c. Zr2 Ni-type phase which can act as heterogenous nucleation sites for the formation of dendrites during solidification. An increase in oxygen content changes the crystallization behaviour from a single- to a double-step process and triggers the crystallization of stable Zr2(Cu,Al) besides metastable Zr2 Ni-type phase. Oxygen-triggered nucleation of a nanocrystalline metastable Zr2 Ni-type phase is found to be the initial step of crystallization. The important parameters of GFA such as glass transition temperatures, Tg, the crystallization temperatures, Tx, and crystallization enthalpies, deltaH, were determined by using DSC. It was observed that the presence of oxygen, even in a very small amount, and Ti addition cause a drastic reduction of the supercooled liquid region, deltaTx, accompanied by a change of the crystallization kinetic. This leads to the decrease in stability of the supercooled liquid, consequently results in a deterioration of the glass forming ability of the alloy.     

Fe60Co8Zr10Mo5W2B15块体非晶合金的形成及热处理对性能的影响研究

用铜模吸铸法获得直径为2mm的Fe60Co8Zr10Mo5W2B15和Fe60Co8Zr10Mo5W2B15块体非晶合金。采用X射线衍射（XRD）、示差扫描量热分析（DSC）、显微硬度及压缩实验等研究了非晶合金的结构、热稳定性及热处理前后的显微硬度与压缩性能。结果表明Nb的引入不利于非晶合金的形成；Fe60Co8Zr10Mo5W2B15非晶合金的显微硬度为1343HV0．2，抗压强度σbe为972．6MPa；在低于晶化起始温度的热处理，硬度稍有下降；但在高于晶化峰值温度的热处理，硬度值随时间变化先升高，后下降；在热处理时间相同的条件下，随着热处理温度的升高，合金的硬度升高，但压缩强度会明显下降。     

Fe_(88-x)Zr_xB_(12)合金的结构及晶化研究

采用机械合金化法制备Fe88-xZrxB12(X=5、10、15、20)系合金,利用X射线衍射仪(XRD)、差热分析仪(DTA)等测试手段对样品的结构及晶化进行研究.XRD结果表明,球磨60h,Fe88-xZrxB12(x=5、10、15)已形成α-Fe固溶体,Fe68Zr20B12完全形成非晶合金,表明Zr含量的增加使合金的非晶形成能力增强.Fe88-xZrxB12(x=5、10、15、20)合金的DTA图中均出现2个晶化放热峰.Fe68Zr20B12非晶合金的晶化模式为一次晶化.     

FeCoBSiNb (Y)合金的玻璃形成能力及磁性能研究

采用铜模真空吸铸法、X射线衍射仪(XRD)、示差扫描量热分析仪(DSC)及振动样品磁强计(VSM),研究稀土元素Y及Fe/Co比例变化对FeCoBSiNb(Y)系合金的玻璃形成能力、热稳定性及磁性能影响.实验结果表明,添加4%(原子分数)的Y有利于(Fe0.5 Co0.5)72B19.2 Si4.8Nb4合金玻璃形成能...     

新型Zr57Nb5Cu15.4Ni12.6Al10大块非晶态合金的制备及其室温单轴压缩断裂行为

应用铜模真空吸铸法制备直径达5mm的棒状新型Zr57Nb5Cu154Ni12.6Al10大块非晶样品.X射线衍射检测证明样品完全为非晶态.通过等温示差扫描量热法(DSC)测试了Zr57Nb5Cu15.4Ni12.6Al10大块非晶的晶化动力学效应,同时研究了大块非晶合金的室温单轴压缩变形和断裂行为.结果表明:Zr57Nb5Cu15.4Ni12.6Al10块体非晶晶化过程具有动力学效应;其室温压缩变形过程主要表现为弹性变形;断裂面与压缩方向约呈45°,断口呈现典型的脉状花样.