Study on interaction mechanism of different atomic ratio of neodymium, arsenic and iron

In this study, neodymium and arsenic were sealed into industrial pure iron cylinders at a temperature of 1223 K for 50 h. The interaction mechanism of the Nd–Fe–As system at various atomic ratios was investigated by optical microscopy, X-ray diffractometry, and scanning electron microscopy. Binary compounds Fe12As5, NdAs, Fe2As, and Fe17Nd2 were the main products formed, with traces of NdFeAs compounds. In addition, at high temperatures, As content affected the diffusion of Fe atoms; the diffusion of Fe increased with an increase in the atomic ratio. Furthermore, the diffusion ability of Nd was weaker than that of As. The major diffusion mechanism of Nd was through the Fe atomic vacancy mechanism. As mainly bind to Fe to form Fe and As compounds. The formation of ternary compounds was confirmed by laboratory experiments and mismatch calculations.

Study on Interaction Mechanism of Different Atomic Ratio of Neodymium, Arsenic and Iron

In this study, neodymium and arsenic were sealed into industrial pure iron cylinders at a temperature of 1223 K for 50 h. The interaction mechanism of the Nd-Fe-As system at various atomic ratios was investigated by optical microscopy, X-ray diffractometry, and scanning electron microscopy. Binary compounds Fe12As5, NdAs, Fe2As, and Fe17Na2 were the main products formed, with traces of NdFeAs compounds. In addition, at high temperatures, As content affected the diffusion of Fe atoms; the diffusion of Fe increased with an increase in the atomic ratio. Furthermore, the diffusion ability of Nd was weaker than that of As. The major diffusion mechanism of Nd was through the Fe atomic vacancy mechanism. As mainly bind to Fe to form Fe and As compounds. The formation of ternary compounds was confirmed by laboratory experiments and mismatch calculations.

Механизм диффузии монооксидов углерода и кремния в кристалле кубического карбида кремния

The basic processes are described occurring in the case of the diffusion of carbon monoxide CO and silicon monoxide SiO through a layer of single-crystal silicon carbide SiC. This problem arises when a single-crystal SiC layer is grown by the method of atom substitution due to the chemical reaction of a crystalline silicon substrate with CO gas. The reaction products are the epitaxial layer of SiC and the gas SiO. It has been shown that CO and SiO molecules decompose in SiC crystals. Oxygen atoms migrate through interstitials in the [110] direction only with an activation energy of 2.6 eV. The migration of Si and C atoms occurs by the vacancy mechanism in the corresponding sublattices with activation energies of 3.6 eV and 3.9 eV, respectively, and also in the [110] direction only.