| This paper aims to review our recently obtained data on the reactions which look like peritectic though there is a difference between them and classical peritectic reactions. Such phase transformation involving a glassy/amorphous/supercooled liquid phase was initially observed in the rapidly-solidified Ge60Al25La15 alloy in which an amorphous and a crystalline phase produce another crystalline phase. Another rapidly solidified Zr65Ni10Al7.5Cu7.5Ti5Nb5 alloy has a mixed structure containing glassy and a submicron β-Zr solid solution phase. The glassy+bcc β-Zr solid solution structure transforms to a mixture consisting of residual glassy and icosahedral phases after the completion of the first exothermic reaction, and this reaction is also a single-type reaction. A common feature of these phase transformation is that they are diffusion-controlled. The reactions described above look, in general, similar to the peritectic one though the absence of the diffusion transfer through the product phase, lack of a common interface and absence of inherited structure differentiate such type of reactions from a classical type peritectic reaction. The structure changes observed and the kinetics of these phase transformations are discussed in detail. Compared to the above-mentioned a reaction glassy+nanoscale I-phase -> cF96 Hf2Fe phase observed in the melt-spun Ti40Zr20Hf20Fe20 alloy is closer to typical peritectic one. |
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