A study on the growth and dissolution of crystals in a peritectic system

通过对硝酸锶-水体系中包晶组织的原位观察，阐明了包晶组织形成的有利条件和机制。尽管α和β相分别在包晶温度以上和以下是稳定的，但α相在任何温度下都是最初形核的，β相是在先前存在的α相上形成的。然而，一旦出现β相，它的生长速度比α相快得多，并包裹了α相。这些结果表明，两相形核和长大的相反特征导致了包晶组织。

We aimed to elucidate the favorable conditions and mechanisms to peritectic microstructure on the basis of the in situ observations of the solidification processes in Sr(NO3)2-H2O system. Although α and β phases are stable at above and below peritectic temperature, respectively, α phase nucleated initially at any temperature and β phase formed on the preexistent α phase. However, once β phase appeared, it grew much faster than α phase and envelop the α phase. These results show that contrary features in nucleation and growth of the two phases induce the peritectic microstructure.