Mechanical alloying of Fe-B

Abstract

Fe-B alloys in both a nanostructural state and a disordered amorphous-like state have been produced using a novel ball-mill method. Mossbauer measurements at room temperature and 4.2 K on materials of nominal starting compositions Fe80B20 to Fe40B60 combined with X-ray diffraction and differential scanning calorimetry, revealed that samples with low B-content (<or approximately=34 at.% B) were formed mainly in a nanostructural state while samples with high B-content (>or approximately=50 at.% B) formed primarily in an amorphous-like state. The detectable B content of the mechanically alloyed samples was found to be lower than the nominal composition for all samples. The presence of unreacted B was confirmed by annealing experiments in which the expected fractions of phases alpha -Fe, Fe2B and FeB were obtained as crystallization products. In the samples, which partially exhibit a nanostructural state, B seems to be present only in the disordered interfacial regions.

Mechanism of formation of Fe–N alloy in the solid-state reaction process between iron and boron nitride

“…The reaction of Fe and B atoms has proved to be difficult to occur in many experiments [12][13][14]. For example, only a small amount of Fe-B amorphous alloy was produced after Fe 100−x B x mixtures (x = 20-40) were milled for 400 h [12], which is much longer than the milling time for the formation of the Fe-N alloy.…”

Nanostructure and Phases Formation under Mechanical Alloying of Bynary Powder Mixtures of Fe and sp-Element (M); M = C,B,Al,Si,Ge,Sn

“…In [25] it was shown that with the content of B of 20 at.% MA was realized during one stage: Fe + B → Fe + Am(Fe-B). At the same time the stage of the amorphous phase formation precedes the formation of borides with a higher amount of B [26][27][28][29][30]. The given data show considerable similarity in the type of SSRs in the Fe-C and Fe-B systems.…”

“…Additional distortions during C dissolution lead to amorphization of the interfaces. MA in the Fe-B system was studied in [25][26][27][28][29][30] with the B content in the initial mixture from 20 to 60 at.%. In [25] it was shown that with the content of B of 20 at.% MA was realized during one stage: Fe + B → Fe + Am(Fe-B).…”

Peculiarities of the Transition to an Equilibrium State of Mechanically Alloyed Fe/Amorphous Phase Fe-B/B Nanocomposite with Composition Fe(68)B(32) upon Thermal Treatment

“…Since the 1970s, amorphous alloys have been prepared in a wide range of boron concentrations, from 10 to 60 at %, by melt quenching and deposition from a gas medium (e.g., see [1,2]); physicochemical properties of the alloys and the structural and phase transformations upon a thermal treatment have been investigated. It is not surprising that, from the 1990s until now, the structure, phase composition, and thermal stability of Fe-B samples prepared by mechanical alloying (MA) have been studied [3][4][5][6][7][8][9][10][11][12][13][14].…”

“…In the most of aforementioned works, structural and phase states were studied using Fe-B samples annealed in a narrow temperature interval or at a single preset temperature after MA. Phases of α -Fe and Fe 2 B were disclosed in samples with compositions of Fe 80 B 20 and Fe 66 B 34 after annealing at 800 ° C [3,4]. A phase of Fe 23 B 6 was found in mechanically alloyed samples with a boron content of 20-25 at % after annealing at 720-900 ° C [12].…”