ISSN 1070-4272, Russian Journal of Applied Chemistry, 2014, Vol. 87, No. 7, pp. 867−871. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © A.F. Dresvyannikov, M.E. Kolpakov, 2014, published in Zhurnal Prikladnoi Khimii, 2014, Vol. 87, No. 7, pp. 872−877.
INORGANIC SYNTHESIS AND INDUSTRIAL
Synthesis of Fe–Al–W Dispersed Polymetallic System
in Aqueous Solutions
and Its Physicochemical Properties
A. F. Dresvyannikov and M. E. Kolpakov
Kazan National Research Technological University, ul. Karla Marksa 10, Kazan, Tatarstan, 420111 Russia
Received July 2, 2014
Abstract—Possibility of obtaining Fe–Al–W polymetallic systems by contact exchange in chloride-containing
aqueous solution was demonstrated. The electrochemical and thermal dependences describing the process occurring
on aluminum microparticles were determined. It is demonstrated that the systems obtained are precursors of
intermetallides, e.g., Fe
Al, FeAl, Fe
Alloys based on iron aluminides belong to a com-
paratively new class of particularly light promising
constructed materials intended for operation above the
working temperatures of titanium alloys . These mate-
rials can be obtained in different ways, including that via
consolidation of dispersed systems containing aluminum
and d-metals. Introduction of tungsten into a system of
this kind makes it possible to improve the heat resistance
and mechanical properties of compact materials .
The difﬁ culty in recovery of tungsten from aqueous
solutions consists, on the one hand, in that W(VI) is
present in aqueous solutions in an anion whose motion to
the cathode is, naturally, hindered. This difﬁ culty is com-
monly tried to be overcome by using various complexing
agents forming positively charged ions incorporating
tungsten. On the other hand, the difﬁ culty consists in the
comparatively low overvoltage of hydrogen evolution at
the cathode, which results in that the evolution of hydro-
gen at the cathode is a dominant process .
The electrochemical deposition of tungsten at the
cathode is possible if the electrolyte contains metals of
the iron family (Fe, Ni, Co) with which it forms alloys.
Presumably, the most adequate among the suggested
explanations of this phenomenon is Vagramyan’s stand-
point according to which a depolarization occurs in joint
discharge of tungsten ions and those of iron-family met-
als because chemical compounds or solid solutions are
formed in the course of deposition .
As a rule, the deposited alloys have high hardness,
corrosion stability, and wear resistance .
As shown in [6–8], a highly dispersed system contain-
ing iron, aluminum, and some d-metals can be obtained
from solutions via contact deposition of metals on alu-
minum microparticles. Further, bulk samples containing
intermetallides, e.g., FeAl and Fe
Al , can be formed
by compaction of this system.
The goal of our study was to examine, using the sug-
gested approach, the possibility of obtaining a dispersed
Fe–Al–W system and compact samples on its basis.
We used aqueous solutions of reagents with quality
characteristics not worse than analytically pure grade:
O and Na
, prepared with distilled water.
Dispersed aluminum of ASD-0 brand (71–100 μm frac-
tion) was taken as delivered. The Al : (Fe + W) molar
ratio in the reaction mixture was 1.5 : 1. The share of
aluminum was brought to the required content by treating
the samples with a concentrated (≥3.0 M) NaOH solution.
The resulting precipitate was isolated by magnetic separa-