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 Ge80Al25 La15 alloy in which an amorphous and a crystalline phase produce another crystalline phase. Another rapidly solidified Zr65Ni10 Al7.5 Cu7.5 Ti5Nb5 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 Ti40Zr20 Hf20Fe20 alloy is closer to typical peritectic one.
|Number of pages||7|
|Journal||Reviews on Advanced Materials Science|
|Publication status||Published - 2008 Dec|