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1.
利用 C-CO 控制反应2[Ce]+3CO=Ce_2O_3+3C 的平衡氧位,使多孔石墨坩埚中[Ce]达到等活度的原理,结合解病态方程组的共轭斜量法,求解了1200℃铜液中 Ce 与 Al、Si、Ti、Fe 的活度相互作用系数,得到了反应3[O]+2[Ce]=Ce_2O_3的平衡常数和铜液中 Ce_2O_3的标准生成自由能。  相似文献   

2.
Cu—Ce—O,Cu—Ce—S,Cu—Ce—O—S溶液体系热力学及其沉淀图   总被引:2,自引:0,他引:2  
杜挺  李国栋 《金属学报》1993,29(7):78-84
本文采用铜液与反应产物直接平衡法,并用固体电解质氧浓差电池和低温无水电解分离反应产物等技术,在1200℃研究了Cu—Ce-O,Cu—Ce-S,Cu—Ce-O—S溶液体系热力学得到了铜液中铈的脱氧、脱硫,脱硫氧常数和平衡产物Ce_2O_3,CeS,Ce_2O_2S的Gibbs标准生成自由能,Ce与S的活度相互作用系数以及Ce的标准溶解自由能和自作用系数与温度的关系式绘制了铜液中[Ce]-[S]-[O]平面沉淀图,确定了铜液中Ce_2O_3,CeS,Ce_2O_2S稳定存在的热力学条件,为预测Ce的夹杂物生成的先后次序及类型提供了理论依据  相似文献   

3.
含有微量O,S,C的Fe—Nb—Ce溶液热力学性质的研究   总被引:2,自引:0,他引:2  
周谦莉  杜挺 《金属学报》1989,25(1):91-95
利用下列组装的固体电解质定氧电池Mo/Cr,Cr_2O_3//ZrO_2(MgO)//[O],Ce_2O_2S/Mo+ZrO_2金属陶瓷,Mo.在1600℃温度下对含微量C的Fe-Nb-Ce溶液进行热力学性质的研究。实验测得1600℃时Fe液中反应Ce_2O_2S=2[Ce]+2[O]+[S]的平衡常数和Ce_2O_2S的标准生成自由能分别为K=4.395×10~(-15),ΔG°_(Ce_2O_2S)=-514.786kJ·mol~(-1);Ce与Nb的活度相互作用系数为e_(Nb)~(Ce)=-2.306,e_(Ce)~(Nb)=-3.481。 随着Nb含量的增加,在微量碳含量的条件下,产物中存在NbC化合物,本文对NbC的生成问题进行了探讨,并得到1600℃时,Fe液中NbC的标准生成自由能为ΔG°_(NbC)=-87.111kJ·mol~(-1)。  相似文献   

4.
The equilibrium product in Fe-Cu-Ce,Fe-P-Ce or Fe-Ti-Ce solution have ben Mentifiedto be Ce_2O_2S,but not the intermetallic compounds of Ce against Cu,P or Ti.The equilibriumeonstant of Ce_2O_2S=2[Ce]+2[O]+[S] and the interaction coefficients between solutes inFe-base solution have been determined as follows:K_(Ce_2O_2S)=2.57×10~(-5)e_(Ce)~(Cu)=-0.49;e_(Ce)~P=1.77;e_(Ce)~(Ti)=-3.62e_(Cu)~(Ce)=-0.22;e_P~(Ce)=0.39;e_(Ti)~(Ce)=-1.23ε_(Ce)~(Cu)=-128.0;ε_(Ce)~P=-224.1;ε_(Ce)~(Ti)=-710.0Ce decreases the activities of Cu and Ti in Fe-base solution and increases their solubifities,aswell as increases the activity of P and decreases its solubility.  相似文献   

5.
Fe—V—Ce溶液的热力学性质研究   总被引:2,自引:0,他引:2  
唱鹤鸣  杜挺  余景生 《金属学报》1989,25(2):152-154
本文研究了在1550—1650℃Fe-V-Ce溶液体系的热力学性质。溶液中微量O,S与Ce建立平衡。已求得Ce与O,S反应的平衡常数。Ce_2O_2S的标准生成自由能及Ce与V的活度相互作用系数与温度的关系。  相似文献   

6.
本文在确定1600℃时CeO_2-CaO-CaF_2和Ce_2O_3-CaO-CaF_2渣系熔化范围的基础上,采用化学平衡法研究渣中稀土氧化物的活度,并绘制等活度线,为选择合理的电渣重熔渣系组成提供理论依据。根据CeO_2在高温低氧分压情况下转变为Ce_2O_3的特性,实验所依据的反应为 (Ce_2O_3) 3C_(石墨)=2[Ce]_(Sn) 3CO 以固态Ce_2O_3和液态Ce作为标准态,炉渣中Ce_2O_3活度的计算公式为αCe_2O_3=[N_(Ce)]~2/[N_(Ce)~0]~2 式中N_(Ce)和N_(Ce)~0分别为与某个组成的渣和与固相Ce_2O_3平衡的Sn中的Ce含量。文中并对在高温低氧情况下CeO_2向Ce_2O_3的转变问题进行了热力学分析。  相似文献   

7.
<正> 本文在确定1600℃时CeO_2-CaO-CaF_2和Ce_2O_3-CaO-CaF_2渣系熔化范围的基础上,采用化学平衡法研究渣中稀土氧化物的活度,并绘制等活度线,为选择合理的电渣重熔渣系组成提供理论依据。 根据CeO_2在高温低氧分压情况下转变为Ce_2O_3的特性,实验所依据的反应为 (Ce_2O_3)+3C_(石墨)=2[Ce]_(Sn)+3CO 以固态Ce_2O_3和液态Ce作为标准态,炉渣中Ce_2O_3活度的计算公式为 αCe_2O_3=[N_(Ce)]~2/[N_(Ce)~0]~2 式中N_(Ce)和N_(Ce)~0分别为与某个组成的渣和与固相Ce_2O_3平衡的Sn中的Ce含量。文中并对在高温低氧情况下CeO_2向Ce_2O_3的转变问题进行了热力学分析。  相似文献   

8.
纯铁液中Ce-O,Nd-O平衡常数的测定   总被引:1,自引:0,他引:1  
自射线照相表明,铁液中的 Ce,Nd 与 MgO,CaO 坩埚均有明显的作用.在保证Ce,Nd 与坩埚充分作用以达到平衡的条件下,应用放射性同位素~(141)Ce,~(147)Nd 及有机电解液电解法测定了铁液中溶解之 Ce,Nd 含量.用 ZrO_2(MgO)管组成的固体电解质电池测定了铁液中溶解氧的活度.计算出1550—1650℃范围内 Ce-O,Nd-O 平衡常数.对于反应 Ce_2O_(3(s))=2[Ce] 3[O]△G*_(Ce_2O_3)451150-161.68TlgK_(Ce_2O_3)=-(98611)/T 35.34对于反应 Nd_2O_3=2[Nd] 3[O]△G*_(Nd_2O_3)=375010-123.7TlgK_(Nd_2O_3)=-(81970)/T 27.04Nd 溶解于铁液的标准自由能 Nd(1)=[Nd]_(1%)△G*_(Nd)=19790-30.40Tlgγ*_(Nd)=(4326.1)/T-4.154  相似文献   

9.
Ni液中Ce-O,Ce-S,Ce-S-O平衡的研究   总被引:1,自引:0,他引:1  
由低温无水电解稀土夹杂物和固体电解质定氧活度测得Ni液中Ce_2O_3,CeS及Ce_2O_2S生成反应的平衡常数,由此可得: △G°_(Ce_2O_3)=-116240+315.8 T △G°_(Ces)=-570280+220.1 T △G°_(Ce_2O_2S)=-984850+238.5 T 由实验测得数据经热力学分析计算得到1600℃Ni液中a_O-a_S平衡图,为理论上预测夹杂物生成的先后次序及类型提供了依据。  相似文献   

10.
用直接法研究1600℃时溶铁中Ce-S-O平衡关系,测定了Ce的脱氧、脱硫、脱硫氧常数,并进行了有关的热力学探讨.由测得数据算出Ce的溶解自由能(△G_溶~0);活度系数(γ_(Ce)~0);克原子分数和百分浓度的交互作用系数ε_(Ce)~(Ce),e_(Ce)~(Ce);生成Ce_2O_2S的自由能△G_(Ce_2O_2S)~0.  相似文献   

11.
In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.  相似文献   

12.
After nearly two years' tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry (SRIF), located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.  相似文献   

13.
The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).  相似文献   

14.
The orientation relationships(ORs)between the martensite and the retained austenite in low-and medium-carbon steels after quenching–partitioning–tempering process were studied in this work.The ORs in the studied steels are identified by selected-area electron diffraction(SAED)as either K–S or N–W ORs.Meanwhile,the ORs were also studied based on numerical fitting of electron backscatter diffraction data method suggested by Miyamoto.The simulated K–S and N–W ORs in the low-index directions generally do not well coincide with the experimental pole figure,which may be attributed to both the orientation spread from the ideal variant orientations and high symmetry of the low-index directions.However,the simulated results coincide well with experimental pole figures in the high-index directions{123}_(bcc).A modified method with simplicity based on Miyamoto’s work was proposed.The results indicate that the ORs determined by modified method are similar to those determined by Miyamoto’method,that is,the OR is near K–S OR for the low-carbon Q–P–T steel,and with the increase of carbon content,the OR is closer to N–W OR in medium-carbon Q–P–T steel.  相似文献   

15.
Tang Dynasty 《中国铸造》2014,(4):I0002-I0003
<正>Bronze mirrors were used by the Chinese people before the introduction of the glass mirror.Only after it was replaced by the glass mirror did the bronze mirror gradually retreat from people's lives.Different styles of bronze mirrors were made in different historical periods,particularly in the Warring States Period,the Han and Tang Dynasties,which were the three peaks of the development of bronze mirror arts in ancient China.The casting techniques were exquisite.The surface of the bronze mirror was smooth and bright enough to reflect one's image,and there were scarcely any casting defects on the mirror surface.On the back of the bronze mirror,there were rich depictions of Arts and Humanities,and the ornamentations were also  相似文献   

16.
《中国铸造》2014,(5):464-466
The 9th China International Diecasting Congress & Exhibition was held on July 22-24, 2014 at Shanghai New International Expc Centre. This exhibition was the most successful over the years, with over 6890 visitors and 155 exhibitors, and the exhibition area increased by 30% from 9,500 square meters in 2012 to 12340 square meters. Die casting enterprises from a total of 24 countries and regions, including China mainland, Chinese Taiwan and Hong Kong, South Korea, Japan, Germany, India, Thailand, Malaysia, the United States, Russia, Australia, Iran, Ukraine, Brazil, Colombia, Singapore, Austria, Canada, Croatia, France, Turkey, United Kingdom, Vietnam, attended the congress and exhibition.  相似文献   

17.
正The Fluid Control Engineering Institute of Kunming University of Science and Technology was set up in 1996.The researches of institute concentrate on electro-hydraulic(pneumatic)servo/proportional control and hydromechatronics.The Institute is committed to research and development of electro-hydraulic control of high-end technical equipment in ferrous metallurgy refining produc-  相似文献   

18.
19.
Antimony induced crystallization of PVD (physics vapor deposition) amorphous silicon can be observed on sapphire substrates. Very large crystalline regions up to several tens of micrometers can be formed. The Si diffraction patterns of the area of crystallization can be observed with TEM (transmission electron microscopy). Only a few and much smaller crystals of the order of 1μm were formed when the antimony layer was deposited by MBE (molecular beam epitaxy) compared with a layer formed by thermal evaporation. The use of high vacuum is essential in order to observe any Sb induced crystallization at all. In addition it is necessary to take measures to limit the evaporation of the antimony.  相似文献   

20.
Fatigue damage increases with the applied loading cycles in a cumulative manner and the material deteriorates with the corrosion time. A cumulative fatigue damage rule under the alternative of corrosion or cyclic loading was proposed. The specimens of aluminum alloy LY12-CZ soaked in corrosive liquid for different times were tested under the constant amplitude cyclic loading to obtain S-N curves. The test was carried out to verify the proposed cumulative fatigue damage rule under the different combinations among corrosion time, loading level, and the cycle numbers. It was shown that the predicted residual fatigue lives showed a good agreement with the experimental results and the proposed rule was simple and can be easily adopted.  相似文献   

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