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1.
根据含化合物金属熔体铁共存理论,相图和Fe-C系亚稳态化合物的有关热力学数据制定了Fe-Si-C熔体的作用浓度计算模型,计算结果符合实际,从而证明所推导的计算模中以反映体熔体的结构实际。  相似文献   

2.
根据含化合物金属熔体的共存理论,Fe-La相图、Fe-O相图,及相关文献的研究成果,确定了Fe-La-O金属熔体的结构单元,进而推导了各组元作用浓度的计算模型.研究表明,计算的作用浓度与相应的实测活度相符合,从而证明所得模型可以反映Fe-La-O金属熔体的结构本质,同时说明计算过程中引用的La2O3的平衡参数"ΔG°=-75 380+17.60T"是准确的.  相似文献   

3.
张鉴 《包头钢铁学院学报》2001,20(3):214-218,231
根据相图、质量作用定律和金属熔体结构的共存理论制定了Mg-Al,Sr-Al和Ba-Al熔体的作用浓度计算模型并求得了相关的热力学参数,计算结果符合实际,证明所制定的模型和确定的热力学参数可以反映相应熔体的结构特点,但将相应文献的热力学参数代入同样熔体则未取得符合实际的结果,原因可能与文献中的热力学参数不符合液态下金属熔体内部化学反应的实际有关。  相似文献   

4.
根据混合自由能有最小值,过剩自由能有最大值(或最小值),激冷条件下产生化合物状亚稳相及共晶,分层等现象,针对Cd-Bi,Ge-Al,Bi-Sn,Cd-Sn,Ag-Cu,Al-Ga;Si-Ag,Pb-Sn和Al-Sn金属熔体推导了作用浓度的计算模型,计算结果与实测值符合较好,从而证明所提出的计算模型符合本类熔体的结构特点。  相似文献   

5.
根据Cd-Sn合金相图、电阻率、热容量、偏摩尔熵和粘度,确定该合金熔体的结构单元为Cd原子,Sb原子以及Cd3Sb2,Cd4Sb3和CdSb化合物。基于以上结构单元,并依据含化合物金属熔体的共存理论,推导了Cd-Sb合金熔体的作用浓度计算模型。理论计算的Ncd,与实测的Cd的活度值a(cd),完全一致。同时也计算出了以上3种化合物的标准自由能。  相似文献   

6.
Fe-Si-C合金熔体的活度解析计算   总被引:1,自引:0,他引:1  
由三元碳饱和合金熔体的碳饱和数据以及其二元子系的精选活度数据作为边界条件,导出了计算三元合金熔体整个液态均相区内务组元活度的解析计算新方法.并用之于Fe-Si-C合金熔体在1873K温度下的活度计算和预测,取得与实验数据吻合较好的结果.  相似文献   

7.
在金属熔体共存理论的基础上,通过舍弃缔合溶液模型中某些经验参数,从理论上系统地制定了如下金属熔体混合热力学参数计算公式混合自由能△Gm=∑x[i∑i=3Ni△Gθi+RT j∑j=1NjlnNj];过剩自由能△GXS=△Gm-RT(aln a+ bln b);混合热焓△Hm= =∑x i∑ i=3 Ni△Hθi;混合熵△Sm=∑x[i∑i=3Ni△Gθi+RT j∑j=1NjlnNj];过剩熵△SXS=△Sm-R(aln a+bln b).计算结果与实测值极为符合,证明这些公式可以确切地反映本熔体的混合热力学性质.金属熔体混合热力学参数计算公式的制定就使金属熔体的热力学模型获得两个实践检验标准(活度和混合热力学参数)及一个理论检验标准(质量作用定律),从而有力地保证金属熔体的共存理论更严格和真实地反映金属熔体的结构实际.  相似文献   

8.
基于炉渣结构共存理论,建立了FeO—Fe2O3-SiO2三元渣系的作用浓度模型,计算了1350℃时的作用浓度NFeO和NSiO2,考察了碱度B对它们的影响,并基于该作用浓度模型对铜闪速熔炼过程进行了多相平衡计算.结果表明,理论计算值NFeO、NSiO2与文献实测值αFeO、αSiO2吻合较好,说明作用浓度模型能较好的反映该渣系的结构本质;与采用经验公式计算的活度系数相比,基于作用浓度模型计算的活度系数,铜闪速熔炼多相平衡模拟结果更接近生产实践,表明将炉渣结构共存理论应用于铜闪速熔炼过程热力学研究是可行的.  相似文献   

9.
利用自由体积理论和新一代几何模型,建立了三元金属熔体活度系数lnγ^oi的模型表达式,计算出1873K温度条件下铁基熔体中组元的活度系数,并将模型计算结果与文献精选数据进行比较,表明活度系数的模型计算结果与文献精选数据相关吻合。  相似文献   

10.
利用自由体积理论和新一代几何模型,建立了三元金属熔体括度系数lnγ0i的模型表达式,计算出1873K温度条件下铁基熔体中组元的活度系数,并将模型计算结果与文献精选数据进行比较,表明活度系数的模型计算结果与文献精选数据相当吻合.  相似文献   

11.
Based on the phase diagram, the coexistence theory of the metallic melt structure involving compoundformation and the regularity of melts containing saturated phase, a calculating model of mass action concentrationsfor Mn-C melts was formulated. According to the activities (or activity coefficients AM. and γc.), obtained by theUnified Interaction Parameter Model (UIPM), the thermodynamic parameters G and G at higher temperatures (1628~1873 K) were optimized by the repeated try and error method. It is testified that G G(873~1273 K) and G (298~1623 K), obtained at lower temperatures, can also be used at the above-mentionedhigher temperatures. The calculated N. and N agree well with ac. and ac obtained by UIPM. This result showsthat the deduced model can reflect the structural reality of Mn-C melts.  相似文献   

12.
According to the results of research on the thermodynamic propelles of Fe-Cr, Fe-P and Cr-P melts, the measured achvihes of Fe-Cr-P melts from reference sources as well as the coexistence theory of metallic melts structure involving compound formation, a calculating model of the mass action concentrations for Fe-Cr-P melts has been formulated and some of its thermodynamic parameters have been optimized. The calculated mass action concentrations agree with the measured achvities, which shows that this model can reflect the structural reality of Fe-Cr-P melts.  相似文献   

13.
An empirical equation of carbon solubility in Fe-Cr-C melts is regressed based on the experimental data from references. Acalculating model of mass action concentrations for these melts is formulated on the basis of the coexistence theory of metaIlic melts in-volving compound formation, the phase diagram of Cr-C system as well as thermodynamic data of Fe-Cr-C melts. According to the mod-el, the standard Gibbs free energies of formation of CrC and Cr3C2 are obtained. Satisfactory agreement between the calculated and me-asured values shows that the model can reflect the structural characteristics of Fe-Cr-C melts.  相似文献   

14.
According to phase diagrams, measured activities as well as the coexistence theory of metallic melts structure involving compound formation, the calculating models of mass action concentrations for Ni-Mn and Co-Mn melts are formulated and their thermodynamic parameters are optimized. As a result, the calculated mass action concentrations agree well with the corresponding measured activities, showing that these models can reflect the structural characteristics of both Ni-Mn and Co-Mn melts.  相似文献   

15.
Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.  相似文献   

16.
Based on the phase diagrams, measured activities as well as△Gm and △GXS, calculating models of mass action concentrations for metallic melts involving monotectic have been formulated. The calculated results agree with practice on the whole, showing that the models deduced generally can reflect the structural characteristics of these melts. The metastable compounds formed in the melts are of the types A2B3, AB2, A2B3or AB and A2B3+AB etc..  相似文献   

17.
Based on the phase diagrams and the coexistence theory of metallic melts structure involving compound formation, the cal- culating models of mass action concentrations for Mn-P and Fe-Mn-P melts have been formulated. The calculated mass action concen- trations agree well with the corresponding measured activities, this in turn shows that the deduced models can reflect the structural char- acteristics of the melts concerned and there isn't any saturation of phosphorus in both melts.  相似文献   

18.
According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi T1 and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.  相似文献   

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