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1.
许茜  于亚鑫 《金属学报》1994,30(4):B150-B155
本文将DCA模型应用于LiF-CaF2,NaF-CaF2和KF-CaF2熔体,并假设在这些熔体中存在络合离子CaF3,利用已有的上述混合熔体量热和熔盐相图的实验数据估计了熔体模型中的参数,并计算了熔体的混合热力学参量及相图,计算结果与实验结果吻合较好。  相似文献   

2.
用目测变温法、差热分析法及X射线粉末法测定了KF─LiC─CaCl_2系熔盐相图,发现KF在LiCl-CaCl_2熔盐溶液中呈负偏差,并对KF-LiCl-CaCl_2系相图和已经研究的KF-LiCl-BaCl_2及KP-LiCl-SrCl_2系相图进行了讨论,发现碱土金属氟化物的初晶面积和溶解能参数之间存在一定的关系.  相似文献   

3.
魏季和  刘宗远 《金属学报》1994,30(20):350-360
利用ZrO_2固体电解质氧浓差电池测定了电渣重熔用CaF_2+Al_2O_3和CaF_2+Al_2O_3+CaO系熔渣的氧渗透率,考察了熔渣成分及温度对熔渣传氧性能的影响.在1673—1873K和0.1MPa的氧气氛下,侧得这两个渣系熔渣的氧渗透率分别为1×10-(20)—6×10-(19)和1×10 ̄(21)—5×10 ̄(18)molO_2·cm ̄(-1)·s ̄(-1);随MnO_2,Fe_2O_3,Cr_2O_3,TiO_2,CaF_2含量和碱度(CaO/SiO_2)的增高,熔渣的氧渗透率增大,MnO_2和Fe_2O_3的影响尤为显著;随温度的升高,熔渣的氧渗透率增大,且可按速率过程来处理CaF2基多元复杂熔渣的传氧过程。  相似文献   

4.
研究了在1723K下CO还原CaO-SiO_2-A1_2O_3-Fe_tO渣系。根据CO_2红外分析仪测定的出口气体中CO_2浓度变化,计算了炉渣的表现还原速度常数K_a和还原速度常数K。结果表明,加入Al_2O_3,提高了CaO-SiO_2-Fe_tO的K_a和K值;炉渣碱度不变时,随着Fe_tO含量的增加,K_a呈增加趋势,但K则呈抛物线趋势变化;当FeO的光学碱度∧_FeO为1.0或0.87时,K_a随该四元渣系光学碱度的增加而线性增加,而K则呈递减趋势。用炉渣规则溶液模型计算了CaO-SiO_2-Al_2O_3-Fe_tO四元渣系的Fe_tO活度a_Fe_tO。  相似文献   

5.
KF—LiCl—CaCl2系相图研究   总被引:1,自引:0,他引:1  
阎立诚  方建慧 《金属学报》1994,30(7):B301-B303
用目测变温法,差热分析法及X射线粉末法测定了KF-LiCl-CaCl2系熔盐相图,发现KF在LiCl-CaCl2熔盐溶液中呈负偏差,并对KF-LiCl-CaCl2系相图和已经研究的KF-LiCl-BaCl2及KF-LiCl-CrCl2系相图进行了讨论,发现碱土金属氟化物的初晶面积和溶解能参数之间存在一定的关系。  相似文献   

6.
黄宗泽  肖兴国  肖泽强 《金属学报》1995,31(19):289-294
在1500℃下,用X射线透视装置研究了CaO-SiO_2-Al_2O_3-FeO熔渣被石墨还原过程中渣的起泡行为,测定了熔渣的起泡指数和起泡率等参数.结果表明,随熔渣碱度上升,其起泡率增大而起泡指数却下降.同时考察了MgO,CaF_2,Na_2O等添加物对熔渣起泡行为的影响.通过对熔渣起泡指数的因次分析得到,熔渣起泡指数与熔渣粘度,密度,表面张力及重力加速度g有如下关系:  相似文献   

7.
戴长虹  张显鹏 《金属学报》1994,30(18):243-246
本文以Sn作熔剂,以石墨作坩埚,在一个半密闭的石墨容器内,用“熔渣-金属”化学平衡法测定了含挥发性组分B2O3的CaO-B2O3二元系中CaO的活度;用α函数积分法计算了B2O3的活度.实验结果与文献报道的利用相图和生成自由能计算得到的数据相符.  相似文献   

8.
沈剑韵 《金属学报》1994,30(16):145-149
由已有热力学和相图实验数据,用Calphad技术优化出一组描述Ga-In-As三元体系热力学性质的数学模型,定量估算了在用外延法制作III-V族化合物时,由于外延层和衬底晶格不匹配,外延分子晶格弹性形变的形变能对固液平衡相图的影响,计算相图和实验结果基本一致.  相似文献   

9.
含挥发组分B_2O_3渣系活度的测定方法SCIEI   总被引:5,自引:0,他引:5  
戴长虹  张显鹏 《金属学报》1994,30(6):B243-B246
本文以Sn作熔剂,以石墨作坩埚,在一个半密闭的石墨容器内,用“熔渣-金属”化学平衡法测定了含挥发性组分B2O3的CaO-B2O3二元系中CaO的活度;用α函数积分法计算了B2O3的活度.实验结果与文献报道的利用相图和生成自由能计算得到的数据相符.  相似文献   

10.
Ca-Dy2O3-Fe体系反应的动力学研究   总被引:1,自引:0,他引:1  
分析了Ca-Dy2O3-Fe体系高温还原-扩散制备DyFe2热力学可能性,应用收缩核模型确定扩散是该体系反应的控制步骤,并进行了XRD,EDX与SEM分析,得知在高温下可用Ca还原Dy2O3生成Dy,Dy向Fe中扩散生成DyFe2,同时求得DyFe2的表观活化能为210kJ/mol。  相似文献   

11.
KF-LiCl-BaCl_2及LiF-LiCl-BaCl_2相图的测定SCIEI   总被引:2,自引:0,他引:2  
本文测定了KF-LiCl-BaCl_2及LiF-LiCl-BaCl_2的伪三元相图。并就改变一价氟化物阳离子半径的变化和相图中初晶区面积的关系进行了讨论。  相似文献   

12.
1.IntroductionTheincreasingdemandsf0rlownitrogensteelproductsgiveriset0greatenthusiaJsmtouseTiO2-basedfluxfordenitrogeniZationofsteel[1-3].ManyexperimentscondrmedthatTi0z-basedslagshavehighernitridecaPacitiesandaPpeartobeonekind0fthemosteffectivefiuxesf0rdeIiltrogenization.Butasfarastherm0dynamicstudiesareconcerned,littleworkhasbeenreported0nthethermodynamiccalculationm0delsforTiO2-base'slags[4],especiallyf0rmulticomponentslagswithtitania-Inadditi0n,aJsaresultofusingvanadium-bearingtitani…  相似文献   

13.
The phase diagrams of molten salt systems KF-LiCI-BaCl_2 and LiCI-LiF-BaCl_2 havebeen determined by visual polythermal method.The relationship between the change of cationradius of monovalent fluoride and the areas of primary crystal region in the phase diagrams isdiscussed.  相似文献   

14.
Based on the practical basis of measured activities and phase diagrams as well as in the light of the mass action law, the model of inseparable cations and anions of molten salts and mattes, and the annexation principle of two kinds of solutions in binary melts, the calculating model of mass action concentrations of molten salts CaCl_2-MgCl_2-NaCl was formulated. The results of calculation not only agree with experimental values, but also obey the mass action law, testifying that the model formulated can embody the structural characteristics of these ternary salts, and that the model of inseparable cations and anions as well as the annexation principle of two kinds of solutions in binary melts are also appficable to these ternary salts.  相似文献   

15.
熔融CaCl2-MgCl2体系的粘度   总被引:2,自引:0,他引:2  
用旋转柱体法系统测量了CaCl2-MgCl2熔融盐体系的粘度,考察了熔融CaCl2-MgCl2体系粘度随温度和组成的变化关系.比较了实验测得的数据与文献报道值,根据熔融盐体系粘度变化规律对熔融体系结构进行了推断.实验测得熔融物体系粘度随温度升高而明显降低,由于所用试剂含有少量杂质,与文献报道的纯CaCl2和MgCl2的粘度值相比,实验测得值出现偏差.熔融CaCl2-MgCl2混和体系的粘度明显要比纯物质的粘度大,这说明在熔融条件下,CaCl2-MgCl2体系生成了体积较大的配合物粒子,增加了熔体粘度.在不同的温度条件下,由于有不同组成的配合物生成,体系粘度最大值对应了不同熔体组分.  相似文献   

16.
Based on the practical basis of measured activities and phase diagrams as well as in the light of the mass action law, the model of inseparable cations and anions of molten salts and mattes, and the annexation principle of two kinds of solutions in binary melts, the calculating model of mass action concentrations of molten salts CaC12-MgCl2-NaCl was formulated. The results of calculation not only agree with experimental values, but also obey the mass action law, testifying that the model formulated can embody the sauctural characteristics of these temary salts, and that the model of inseparable cations and anions as well as the annexation principle of two kinds of solutions in binary melts are also applicable to these ternary salts.  相似文献   

17.
The phase diagrams of the Li2MoO4-Na2MoO4 and Na2MoO4-K2MoO4 systems have been reassessed using differential thermal analysis together with high-temperature and room-temperature X-ray diffraction analysis. The results showed that the compound Li2MoO4.6Na2MoO4 did not exist; however, it confirmed the existence of the compound Li2MoO4.3Na2MoO4 in the Li2MoO4-Na2MoO4 systen'ls. With regard to the system of Na2MoO4-K2MoO4, we could not confirm the results reported by Bukhanova who claimed that the system was eutectic type with 1:1 and 1:2 intermediate compounds, refuting the statement of Amadori who thought there was an apparent phase boundary at high temperature in α-solid solution region of the Na2MoO4-K2MoO4 binary system. The revised phase diagrams of these systems are illustrated in this article. These experimental results are in agreement with the computerized prediction using the support vector machine-atomic parameter method for the assessment of phase diagrams.  相似文献   

18.
根据炉渣结构的共存理论和相图,推导了CaOB2O3和FeOFe2O3B2O3渣系的热力学计算模型。结果表明:(1)理论计算的CaOB2O3渣系的作用浓度NCaO及NB2O3与实测的活度aCaO及aB2O3一致;(2)理论计算的FeOFe2O3B2O3渣系的氧化能力NFetO与实测的炉渣FetO的活度值相符合。这说明本文提出的热力学计算模型是合理的。  相似文献   

19.
利用Calphad技术和应用Pandat相图计算软件,重新评估了Al-Si-Fe体系液相投影图,550、727、800℃等温截面,以及不同成分合金在1 477℃时的液相混合焓。结果表明,计算所得相图及液相混合焓与实验数据相符,该工作建立的热力学模型及参数可作为外推建立Al-Zn-Si-Fe等高元体系数据库的基础,并对相关体系的材料设计工作具有重要的指导意义。  相似文献   

20.
1.IntroductionIn0rdert0c0mpensateforash0rtc0ming0fclassicaltherm0dynamics,manyempiricalorsemiempiricalmodelsbased0nthethe0ryofregularsolutionshavebeendevel0pedforpredictingthethermodynamicpr0pertiesofternaryandevenmulticomponentmoltenslags[l'2].Ac0mmoncharacteristic0fthemist0usem0reempiricalappr0aches.Ifonlybinarydataareusedtopredictthetherm0dynamicpr0pertiesofaternarysystem,thedeviationsofpredictedvalueswillbelarger;ifthevauesneedtomatchtherequiredaccuracytaporti0n0fexperimentaldataofaternary…  相似文献   

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