Peritectic compound

Instability of the compound formation brought about through electronic consideration - whether it be eutectic, eutectoid or peritectic compound is the cause for the inherent instability. Subsequently, this inherent instability is the reason for grain size being small,... 

Aluminium, gallium and indium nitride belong to a family of materials described as peritectic compounds. A peritectic compound is defined as a compound that transforms, at the peritectic temperature and atmospheric pressure, according to the reaction ... 

Preparation of a peritectic compound requires a solid state (solid-solid) or solid-liquid reaetion. A solid state reaction requires transport of matter (diffusion) in the direetion of a chemical potential gradient (i.e., a chemical composition gradient). Thus solid state reactions are diffusion controlled, with diffusion fastest across grain boundaries. Within a crystal, diffusion is enhanced by defects. Clearly the preparation of a peritectic alloy should be carried out at the highest possible temperature just below the peritectic decomposition temperature. The speciality of powder metallurgy exploits the optimum conditions for solid state reactions. 

Over the concentration range 50-90 st.% tellurium, effects have been established at 390 C by thermal analysis which are probably associated with the presence of a second peritectic compound havit a nominal formula of hiAsTes, which forms a eutectic with tellurium at 365 C. 

In the quasi-binary section La2Se3-Sb2Sc3 (Aliyev et al. 1977), the peritectic compound is formed at 650°C,... 

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