反应合成制备Ag-Sn-O系电接触材料热力学分析

Thermodynamic Analysis of Ag-Sn-O Electrical Contact Material by Reaction Synthesis Processing

运用GibbsHelmholtz方程进行了反应合成法制备AgSnO2复合材料的热力学计算和数据分析。结果表明:当反应温度小于505K时,反应合成属于固-固间的置换反应;当反应温度大于505K时,反应合成属于固-气间的氧化反应。通过计算500K^1200K范围内生成物SnO,SnO2单位体积生成自由能和分解氧分压,确定以Ag2O,Ag,Sn等为原料,反应合成的最终产物为Ag和SnO2,不存在SnO相。通过数据分析为制定反应合成法制备AgSnO2复合材料的工艺参数提供了理论依据。

A thermodynamic calculation and data analysis were carried out for silver tin oxide composite material prepared by reaction synthesis processing using Gibbs Helmholtz equation. The results show that the reactive temperature is below 505 K, the reactive synthesis of silver tin oxide belongs to the substitution reaction of solid-solid. When the reactive temperature is over 505 K, the reactive synthesis of silver tin oxide belongs to the oxidation reaction between oxygen and solid. By the calculation of free energy per unit volume and decomposed oxygen partial pressure of SnO, SnO2 in the rang from 505 K to 1200 K, it can be determined that the final production is Ag phase and SnO2 phase for the oxygen reaction of Ag2O, Ag, Sn. But no SnO phase exists in the material. The analysis of thermodynamics calculation data and oxygen branch-pressure offers an academic foundation for preparing AgSnO2 composite material adopting reaction synthesis processing.