基于Pandat的Ti-Al系相图计算及热力学评估

摘要

Phase diagram of Ti-A1 system was researched through the calculation using Pandat 2016 thermodynamic calculation software,the latest database of Ti alloy and reasonable thermodynamics models based on Phase diagram calculation theory.The calculated phase diagram was then assessed by phase rule,by analysing the specific points of the phase diagram,the phase areas,the phase transition points and so on.The calculated results show that the calculated phase diagram matches experimental phase diagram very well,laying a foundation for extrapolated phase diagram of ternary system and more.Their relative errors are almost below 5％.As compared with the empirical formula for (α-+-β)/β phase transition points of Ti-A1 system,the new calculated formula proposed is more accurate,having some reference value and academic significance.Its confidence level is 99.982％.%基于相图计算理论,用Pandat 2016热力学计算软件、最新的钛合金数据库和热力学模型,计算研究了Ti-A1二元系相图.从相律、相图的特殊点、各相存在的范围、相变点等方面对其进行了详细的热力学评估.计算结果表明:计算相图和实验相图吻合得较好,其相对误差基本都在5％以内,为推广到三元或更高元体系相图奠定了基础.随后提出了一个新的计算Ti-A1二元系中(α+β)/β相变点的公式,其置信度为99.982％,与经验计算公式相比,计算更为准确,具有一定的参考价值和学术交流意义.