Article history: Received: 28.11.2012. Received in revised form: 04.01.2013. Accepted: 15.01.2013. The microstructural evolution of the coexistence of spinodal decomposition and ordering is characterized by metallographic microscopy and transmission electron microscopy in aged Fe-23Al (i.e. Fe-23at%Al) alloy. This paper discusses a phase transition mechanism of the microstructure evolution. The...

A carbon tool steel plate was coated with an aluminum foil a thickness of 100 μm by explosive welding. This aluminum-coated heat-treated in the temperature range 973−1273 K for up to 3.6 ks atmosphere form Fe-Al alloy layer on surface. The basically composed Fe2Al5, two kinds FeAl (Al-rich and Fe-rich FeAl), Fe3Al containing (Fe3Al(C)) ferrite stabilized diffusion (α-Fe(Al)). FeAl2 also detecte...

This work evaluates the suitability of iron aluminide coatings for use in high temperature fossil fuel combustion environments, such as boiler applications. The coatings are applied using High Velocity Oxy-Fuel (HVOF) thermal spray techniques. Bulk Fe3Al coatings are known to exhibit excellent oxidation and sulfidation resistance at high temperatures, however, the behavior of HVOF-deposited Fe3...

the synthesis of nanocrystalline fe3al powder by mechanical alloying as well as the structural ordering of the synthesized fe3al particles during the subsequent thermal analysis were investigated. mechanical alloying was performed up to 100 hours using a planetary ball mill apparatus with rotational speed of 300 rpm under argon atmosphere at ambient temperature. the synthesized powders were cha...

We explored the B-C-O system at pressures in the range 0-50 GPa by ab initio variable-composition evolutionary simulations in the hope of discovering new stable superhard materials. A new tetragonal thermodynamically stable phase B4CO4, space group I4[combining macron], and two low-enthalpy metastable compounds (B6C2O5, B2CO2) have been discovered. Computed phonons and elastic constants show th...

A first-principles study of the vibrational modes of PbTiO3 in the ferroelectric tetragonal phase has been performed at all the main symmetry points of the Brillouin zone ~BZ!. The calculations use the local-density approximation and ultrasoft pseudopotentials with a plane-wave basis, and reproduce well the available experimental information on the modes at the G point, including the LO-TO spli...