(中南大学 材料科学与工程系，长沙 410083)
摘 要: 根据相区邻接规则和扩散偶中的相区分布的关系，运用三元扩散偶方法确定三元系中的四相转变从而导出三元系中相转变与扩散偶中相区分布的关系；利用Nb-Ti-Si三元系的实验，验证了包共析型转变前后等温截面与扩散偶中相区分布的关系。
关键字: 等温截面；相区分布；四相平衡
in diffusion triple and quaternary
phase equilibria
（Department of Materials Science and Engineering，
Central South University，Changsha 410083，China）
Abstract:According to the principle of adjoining phase fields and the distribution of phase fields in diffusion couples，relation between phase transformation in ternary system and the phase fields distribution in diffusion couples is derived；the experiment of Nb-Ti-Si proves the relation between the change of isothermal sections of peritectoid-eutectoid reaction and the phase fields distribution in Nb-Ti-Si diffusion couples.
Key words: isothermal section；distribution of phase fields；quaternary phase equilibria
