【摘要】 利用电化学法对Fe-Nb熔体中Nb的活度在三个温度下进行研究,采用下列的固体电解质电池:Mo|Mo,MoO₂||ZrO₂（MgO）||[Nb],NbO₂|Mo+ZrO₂金属陶瓷,Mo对测定的α_o数据进行加工处理,求出下列结果: 1.脱氧反应的自由能 [Nb]+2[O]=NbO_2（s）;△G°=-375350+118.28T,J 2.Nb在铁液中的溶解自由能 Nb_s=[Nb]％;△G°=-134260+33.05T,J;γ°₁₈₇₃=1.60 Nb₁=[Nb]％;△G°=-161160+42.84T,J;γ°₁₈₇₃=0.92 3.Nb本身的活度相互作用系数当[Nb]含量大约低于0.2％时,脱氧产物和其它合金元素如Al、Cr、V等相似,形成了复合氧化物如FeO·NbO₂。后者的生成自由能估计为:随着熔体中[Nb]含量的继续下降,对生成其它脱氧产物的可能性,本文也进行了讨论。更多还原

【Abstract】 The activity of Nb in molten iron was studied at three temperatures,1823,1853 and 1873 K.With the electrochemical method,the following solid electrolyte cell assembly being adopted:Mo Mo,MoO₂‖| ZrO,（MgO） || [Nb],NbO,| Mo,Mo+ZrO,cermet.To equilibrate the [O] content of the Nb-containing iron,pure solid NbO,was scattered over the surface of the melt under highly purified argon atmosphere,and in some cases; the surface of the melt was left bare,the oxide as the deoxidation product,which was thermodynamically ascertainedas NbO₂,being formed by itself.By elaboration of the experimental data of αo determined,thefollowing results were obtained: 1. The free energy of the reaction of deoxidation: [Nb] + 2[O] =NbO₂（s）;△G⁰=-375350 +118.28T.J 2. The free energy of solution of Nb in liquid iron: Nb（s）=[Nb]％; AG°=-134260+33.05T J; Vi°,7!=1.60 Nb（l）=[Nb]%; AG°=-161160+42.84r J; Y’,7,=0.92 3. The self activity interaction coefficient of Nb in liquid iron: When the [Nb] content in the molten iron was less than 0.2%,similar to the behavoir of otheralloying elements such as Al,Cr,V etc.,a compound oxide,probably FeO-NbO2 was formed.Itsfree energy of formation from its elements was estimated to be: Fe（1）+3/2O₂+Nb（s）=FeO.NbO₂（s）;AG°=-1605800+510.24T,J As the [Nb] content in the molten iron was decreased still further,the possibility of the pre-sence of other deoxidation products,such as Nb2O5,FeO’Nb2O5,was also briefly discussed.更多还原