低Cu的Al-Zn合金在300℃时平衡相组成及稳定性

通过组织观察与X射线衍射分析,对熔制的Al-20Zn-5Cu合金(摩尔分数/%)铸锭在300℃保温不同时间后的试样组织结构进行了研究.结果发现铸锭中的ε相在300℃保温时完全转变成了细小的T'相,意味着此时的平衡相组成为α1,α2和T'相.而α1和α2相在冷却或室温放置时析出了β相,这意味着采用常规平衡合金法不适于测量α1,α2和T'相的平衡相成分.     

强磁场对铁基合金相变温度和显微组织的影响

The effect of a high magnetic field up to 30 T on phase transformation temperature and microstructure of Fe-based alloys has been reviewed. A high magnetic field accelerates ferrite transformation, changes the morphology of the transformed microstructures and increases the As and A1 temperature. In a magnetic field of 30 T, the A1 temperature increases by about 37.1℃ for Fe-0.8C, the A3 temperature for pure Fe increases by about 33.1 ℃. The measured transformation temperature data are not consistent with calculation results using Weiss molecular field theory. Ferrite grains are elongated and aligned along the direction of magnetic field in Fe-0.4C and Fe-0.6C alloys by ferrite transformation, but elongated and aligned structure was not found in pure Fe, Fe-0.05C alloy and Fe-1.5Mn0.11C-0.1V alloy.     

Cu—Zn—Al系合金热弹性马氏体相变的热滞

本文通过热处理工艺及添加第四组元研究了Cu－Zn－Al系记忆合金的相变热滞。结果表明，淬火冷却速度影响合金的相变热滞大小，随着母相时效时间的延长，马氏体相变热滞变大．Mn元素的加入可以减小CU－Zn－Al合金相变热滞．     

Al-Zn、Al-Cu二元合金系烧结过程的对比研究

利用高温光学金相显微镜对由纯铝粉、纯锌和纯铜粉制成的二元合金粉末体系进行了原位烧结试验.原位观察结果对比研究表明:两种体系烧结的典型物理过程既有共性,又有差异,晶界扩散在烧结过程中始终起着非常重要的作用;这些结果为进一步合理制定和优化烧结工艺提供了直接的试验依据.     

WC-(Ni-Fe)伪二元系局部相图的测定

用光学显微镜、电子显微镜、图像仪、X射线衍射相分析、热差分析等综合方法,研究了WC-(Ni-Fe)系合金,在WC含量(质量分数为6%~38%)范围内的伪二元系相图特征.同时研究了WC在γ相中的最高溶解度和室温溶解度数据.结果表明,WC-(Ni-Fe)伪二元系相图仍属于典型的二元共晶型相图,γ相中的溶解度随温度而变化,共晶温度下最大溶解度(质量分数)为11.2%,室温时最大溶解度为9.01%.     

基于相图解析多组元粒子的奥斯特瓦尔德熟化

The coarsening of particles dispersed in a solution was found by Ostwald in 1900. Then, the following cubic law between mean radius (r) and annealing time (t) was established by Lifshitz-Slyozov and Wagner in 1961.-r3--r3/0=[8σVCW/9RT]XαB·t It should be noted, however, that the above equation is valid in the coarsening of B particles in A-B solution. Therefore, some modification is necessary in the case of multi-component materials. For instance, the coarsening of (Fe,Cr)aCb in γFe-M-C matrix is described as follows[1,2] ;-r3--r3/0=[8σVCW/9RT][a b/a]urM/(uoM-urM)2·t According to Eq. (2), the coarsening rate of M23C6 in heat-resistant steel (9%Cr-1%W-0.1%C) depends on the diffusion rate of Cr, because uαCr/(uθCr- uαCr)2＜＜uαw/(uθw- uaw)2. However, experimental data inform us that the rate-determining element is not Cr but W as shown in Fig. 1[3].Fig.1 Effect of W on coarsening of heat-resistant steel Fig.2Equilibrium between M23C6 in this case The problem is solved by modifying the formula of M23C6 from (Fe, Cr, W)23C6 to Fe4 (Cr, W)19C6 in this case(Fig. 2). Consequently, the coarsening equation is expressed as follows.-r3--r3/0=[8σVCW/9RT][29/23][uaW/uow-uaW][1-uaCr-uaW/(19/23)-uaCr-uaW]·t     

(Cu,Ni)S—FeS—FeO—Me°(合金)系中金属合金的析出

<正> 一、前言铜镍生产中产出的转炉渣是提钴的重要原料之一。由于它含钴品位比较低,因此,无论采用何种方法提钴,必须先制备钴的富集物。金川铜镍转炉渣采用电炉贫化—金属化钴冰铜缓冷—选矿富集工艺制备富钴合金是一种有效的途径。该工艺的特点在于电炉     

Cu—C—Ti系和Cu—CuO—Al系合金粉末的机构合金化

将Ｃｕ－Ｃ３．３％－Ｔｉ１３．３％和Ｃｕ－ＣｕＯ２．５％－Ａｌ１．１％二合金粉末分别进行机械合金化，结果发现，经２０ｈ球磨后，Ｃ的衍射峰已经消失，Ｔｉ，Ａｌ，ＣｕＯ的衍射峰强度显著降低；６０ｈ球磨后，二合金粉末都形成了Ｃｕ基过饱和固溶体；１００ｈ球磨后，部分Ｔｉ，Ｃ，Ａｌ，Ｏ溶质元素脱溶析出，并反应生成ＴｉＣ和Ａｌ２Ｏ３。     

Co-Al二元系中的fcc/hcp马氏体相变和形状记忆效应

It is known that pure Co undergoes martensitic transformation from γ phase (fcc) to ε phase (hcp) by the movement of a/6<112> Shockley partial dislocations at around 400 ℃, however, there have been few systematic works on the SM effect in Co and Co-based alloys. In this study, the fcc/hcp martensitic transformation and the SM effect were investigated in Co-Al binary alloys(mole fraction of Al=0～16%).The γ/ε martensitic transformation temperatures were found from the DSC measurements to decrease with increasing Al content, while the transformation temperature hystereses were observed to increase from 60 ℃ at x(Al)=0 to 150 ℃at x(Al)= 16%. The SM effect evaluated by a conventional bending test was enhanced by the addition of Al over 4%(mole fraction) and Co-Al alloys containing over 10%(mole fraction) exhibit a good SM effect associated with the hcp →fcc reverse transformation above 200 ℃. The SM effect was significantly improved by precipitation ofβ (B2) phase and the maximal shape recovery strain of 2. 2% was obtained, which can be explained by precipitation hardening. The crystallographic orientations between theβ, ε and γ phases were also determined. Finally, the magnetic properties were investigated and it was found that the Curie temperature and saturation magnetization of Co-14% Al(mole fraction) are 690 ℃and 120 emu/g, respectively. It is concluded that the Co-Al alloys hold promise as new high-temperature and ferromagnetic SM alloys.     

Fe(Ⅲ)-Mn(Ⅱ)-As(Ⅴ)-H2O系相图的建立

依据实验数据利用DIASTAB计算机程序,建立了Fe(Ⅲ)-Mn(Ⅱ)-As(Ⅴ)-H20系的稳定性相图.所建立的相图表明,在pH=3.5～6.0范围内,体系内稳定存在的固体化合物为Fe(Ⅲ)-Mn(Ⅱ)-As(Ⅴ)化合物、MnHAsO4和Mn3(AsO4)2,用DIASTAB计算机程序对实验数据进行逼近计算,算得前者的生成自由能为-245.5kcalmol-1;相图还表明,依靠所研究的体系,水相除砷不可能达到WHO规定的砷最大污染值0.05mg/L的标准.     

镁的合金化与合金相图

论文分析了镁基合金二元和多元相图的研究现状；指出了镁合金在合金化中存在的问题。在此基础上探讨了在镁合金的设计与研究过程中如何进行相图的研究。指出由6－10个元素组成镁合金集团进行合金相图的实验测定和热力学计算的方案是可行的。     

Cu基亚稳难混溶合金液-液相变

通过气体雾化技术研究了Cu_100-XFe_X(X=15,20,30和40)合金的凝固行为.考虑少量相液滴形核、扩散长大、空间迁移、凝固界面与液滴间的相互作用以及体积分数等共同影响因素,建立了能描述该类合金凝固组织演变动力学模型.将数学模型与雾化液滴飞行过程中运动、传热和传质的控制方程相耦合,给出了数值求解方法,模拟计算了Cu基亚稳难混溶合金液-液相分离过程.结果表明:富Fe粒子的平均尺寸随着Fe含量的增加而增大;少量相液滴形核发生在基体熔体过饱和度峰值附近;随着冷却速度的增大,雾化液滴中少量相液滴的形核率增大,但平均半径减小;少量相液滴在Marangoni迁移和与固/液界面相互排斥共同作用下,向雾化液滴中心迁移,使雾化粉末最终形成壳型组织结构.     

LiF-NaF-KF体系的相图计算

基于CALPHAD技术首先评估了LiF-NaF和LiF-KF两个二元熔盐体系,液相和端际固溶体Halite相均采用Redlich-Kister多项式置换熔体模型描述,模型参数的优化选取实验相平衡数据和热化学数据以及本文根据第一性原理预测的数据.结合文献中已报道的NaF-KF体系的热力学参数,用Muggianu模型扩展至LiF-NaF-KF三元体系,根据三元共晶点的实验数据调整三元交互参数.最终的相图计算结果与绝大部分实验数据和第一原理计算数据吻合较好,由此获得了一套自洽且可靠的热力学参数,其能够准确描述LiF-NaF-KF体系的相平衡与热力学性质.     

Titanium-boride eutectic materials. Structure of the Ti-Nb-B alloys and phase equilibria

The structure of Ti-Nb-B alloys that are cast and annealed at subsolidus temperatures and at 1400°C is experimentally analyzed (x-ray diffraction, metallography, and electron probe microanalysis), and so are temperatures of their phase transformations (differential thermal analysis and pyrometry). No ternary phases are found in the alloys. Projections of solidus and liquidus surfaces, an isothermal section at 1400°C, and a vertical section at 7.5 at.% B are constructed. A reaction scheme is proposed for alloy crystallization. __________ Translated from Poroshkovaya Metallurgiya, Vol. 46, No. 1–2(453), pp. 72–87, 2007.     

Phase diagram of Er-Sn-Te system for diluted magnetic semiconductor developments

Phase diagrams of the RE (rare earth)-IV-VI systems are very important for the design of rare earth doped diluted magnetic semiconductors (DMSs), but related information is very limited. In this work, ...     

Phase diagram of the Al2O3-ZrO2-Er2O3 system. II. Phase diagram liqiudus surface

The liquidus surface for the Al₂O₃-ZrO₂-Er₂O₃ phase diagram is projected for the first time onto a concentration triangle. No ternary compounds are found in the system. The liquidus surface is completed by eight primary crystallization fields. Four four-phase nonvariant eutectic equilibria, one four-phase nonvariant transformation equilibrium, and three three-phase nonvariant eutectic equilibria are found in the system. Since ZrO₂ interacts with other phases eutectically, the unique properties of ZrO₂-based T-and F-solid solutions can be combined with the properties of other phases of the ternary system in composite materials. __________ Translated from Poroshkovaya Metallurgiya, Vol. 46, No. 1–2(453), pp. 64–71, 2007.     

Phase diagram of the Al2O3-ZrO2-Er2O3 system. III. Solidus surface and phase equilibria in alloy crystallization

The solidus surface for the Al₂O₃-ZrO₂-Er₂O₃ phase is projected for the first time onto the concentration triangle. It consists of five isothermal three-phase fields that correspond to four invariant eutectic equilibria, one invariant transformation equilibrium, and six ruled binary eutectic solidus surfaces. The highest solidus temperature in the system is 2710 °C, which is the melting point of pure ZrO₂, and the lowest is 1720°C, which is the melting point of the ternary eutectic AL + F + Er₃A₅. Neither ternary phases nor visible solid solution areas based on components and binary compounds are found in the system. Based on the data on bounding binary systems, liquidus, and solidus surfaces, the phase equilibrium diagram and reaction scheme for equilibrium crystallization of Al₂O₃-ZrO₂-Er₂O₃ alloys are constructed. __________ Translated from Poroshkovaya Metallurgiya, Vol. 46, No. 5–6 (455), pp. 74–83, 2007.     

Mg_(91.4)Zn_(7.2)Y_(1.4)合金中的相变及相平衡

采用热分析以及合金平衡组织结构分析,对Mg-Zn-Y系Mg_(91.4)Zn_(7.2)Y_(1.4)合金中的相变及其相关相平衡进行了研究.结果表明,Mg_(91.4)Zn_(7.2)Y_(1.4)合金在440℃时处于α-Mg固溶体和准晶I的两相平衡;450℃时处于α-Mg固溶体、液相Liq和三元化合物W的三相平衡.Mg_(91.4)Zn_(7.2)Y_(1.4)合金在446.8℃时发生了I+α-Mg→Liq+W四相包共晶转变.温度超过477.3℃,Mg_(91.4)Zn_(7.2)Y_(1.4)合金中W相不再稳态存在,500℃时合金处于α-Mg和液相两相平衡.