Influence of high-energy ball milling on reaction kinetics in the Ni-Al system: An electrothermorgaphic study

Непапушев, А. А.; Kirakosyan, Kh.G.; Moskovskikh, Dmitry; Kharatyan, S. L.; Рогачев, А. С.; Mukasyan, Alexander S.

doi:10.3103/s1061386215010082

Cited by 21 publications

(12 citation statements)

References 13 publications

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“…The HSTS setup was utilized for the kinetic investigations of the NiO-WO 3 -Mg-C and NiWO 4 -Mg-C precursor mixtures under the programmed linear heating rates, up to 1200 • C min −1 and temperatures up to 1300 • C, which are closer to heating rates and temperatures in the combustion wave at the synthesis of alloys [17][18][19].…”

Section: Methodsmentioning

confidence: 99%

“…To tackle this challenge, the process in the NiO-WO 3 -Mg-C and NiWO 4 -Mg-C systems was preliminary modeled by DTA/TG (Differential Thermal/Thermogravimetric) technique, which is relatively far from the conditions existing in SHS process, but provides primary knowledge about the main stages and intermediates. To reveal the reduction mechanism in the systems under study at conditions closer to heating rates and temperatures in the combustion wave at synthesis of alloys, the process was tuned within the time and the Ni-W formation pathway was explored under programmed linear heating by thermal analysis methods, namely using high-speed temperature scanner (HSTS) [17][18][19].…”

Section: Introductionmentioning

confidence: 99%

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Joint Reduction of NiO/WO3 Pair and NiWO4 by Mg + C Combined Reducer at High Heating Rates

Zakaryan

Nazaretyan

Aydinyan

et al. 2021

Metals

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Functional features of Ni-W composite materials combined with successful performance enabled a breakthrough in their broad application. To disclose the formation pathway of Ni-W composite materials at extreme conditions of combustion synthesis in the NiO-WO3-Mg-C and NiWO4-Mg-C systems for the optimization of the synthesis procedure, the process was modeled under programmed linear heating conditions by thermal analysis methods. The reduction kinetics of tungsten and nickel oxides mixture and nickel tungstate by Mg + C combined reducer at non-isothermal conditions was studied at high heating rates (100–1200 °C min−1) by high-speed temperature scanner techniques. It was shown that when moving from low heating to high heating rates, the mechanism of both the magnesiothermic and magnesio-carbothermic reductions of the initial mixtures changes; that is, the transition from a solid-solid scheme to a solid-liquid scheme is observed. The strong influence of the heating rate on the reduction degree and kinetic parameters of the systems under study was affirmed. The simultaneous utilization of magnesium and carbon as reducers allowed the lowering of the starting and maximum temperatures of reduction processes, as evidenced by the synergetic effect at the utilization of a combined reducer. The effective values of activation energy (Ea) for the reactions proceeding in the mixtures NiO + WO3 + 4Mg, NiO + WO3 + 2.5Mg + 1.5C, NiWO4 + 4Mg and NiWO4 + 2Mg + 2C were estimated by Kissinger isoconversional method and were 146 ± 10, 141 ± 10, 216 ± 15 and 148 ± 15 kJ mol−1, respectively.

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Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Joint Reduction of NiO/WO3 Pair and NiWO4 by Mg + C Combined Reducer at High Heating Rates

Zakaryan

Nazaretyan

Aydinyan

et al. 2021

Metals

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“…A comparative overview allowed us to comment on the strong dependence of microstructure evolution on mechanical and ultrasonic agitation. For example, intense HEBM (694 rpm, 40:1 ball-powder ratio, 6 mm steel balls as a milling media) resulted in the formation of a fine lamellar composite structure and a decrease in reaction onset temperature up to 573 K after 5 min MA [32]. It was obvious that the interaction started during the milling and would not achieve the homogeneous phase and microstructure formation, as well as an accurate determination of the activation energy value.…”

Section: The Calculation Of Effective Activation Energy Of the Ni + A...mentioning

confidence: 99%

The Interaction Pathway in the Mechano-Ultrasonically Assisted and Carbon-Nanotubes Augmented Nickel–Aluminum System

Nazaretyan

Kirakosyan

Zakaryan

et al. 2022

Metals

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The influence of mechano-ultrasonic activation (MUA) and nano-additives (carbon nanotubes-CNT) on the interaction pathway of nickel–aluminum powder mixture at high heating rates was investigated. The optimum conditions of the mechano-ultrasonic activation, along with the phase and structure formation peculiarities of nickel–aluminum and nickel–aluminum–carbon nanotubes mixtures by thermal analysis method, the so-called high-speed temperature scanner (HSTS), were found out. The optimum duration of mechanical and ultrasonic activation aiming to achieve homogeneous distribution in the agitated mixtures was determined. A shift in characteristic temperatures of MUA mixtures by the influence of both heating rate and ultrasound on the Ni + Al interaction pathway for the mechano-activated (1, 3, 5 min) and 1 wt% CNT containing mixtures was observed. The formation patterns of NiAl + Ni3Al mixture or pure NiAl phase was manifested according to the interaction mechanism (depending on solid–liquid or solid–solid state of intermediates). The effective activation energy values for the Ni + Al exothermic reactions of all studied systems were determined by the isoconversional method of Kissinger.

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“…They reported an unusually low activation energy of 9.5 ± 2 kJ/mol. Nepapushev et al studied the kinetics of ball-milled nanostructured Al/Ni composites by electrothermography 43 with a heating rate of 4.5−45 K/s. Interestingly, the reaction onset temperature and the temperature of maximum reaction rate decreased with increasing the heating rate.…”

Section: Introductionmentioning

confidence: 99%

Kinetics and Mechanism of Ignition in Reactive Al/Ni Nanostructured Materials

Manukyan¹,

Pauls²,

Shuck³

et al. 2018

J. Phys. Chem. C

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A high-speed electrothermography approach is applied to investigate the mechanism and kinetics for nanostructured Al/Ni foils. Application of the Kolmogorov−Johnson−Mehl−Avrami and adiabatic thermal explosion models reveal that the activation energy for nucleation appears to be much higher than that for the reaction. It is shown that formation of intermetallic nuclei is the limiting step that defines the ignition characteristics of the foils at temperatures below 500 K, while the process is reaction-limited at higher temperatures. Nucleation is also shown to play an important role during rapid (∼10 m/s) propagation of the combustion (reaction) wave along the Al/Ni foils. These findings suggest new approaches for controlling the ignition and combustion processes for nanostructured reactive materials.

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Influence of high-energy ball milling on reaction kinetics in the Ni-Al system: An electrothermorgaphic study

Cited by 21 publications

References 13 publications

Joint Reduction of NiO/WO3 Pair and NiWO4 by Mg + C Combined Reducer at High Heating Rates

Joint Reduction of NiO/WO3 Pair and NiWO4 by Mg + C Combined Reducer at High Heating Rates

The Interaction Pathway in the Mechano-Ultrasonically Assisted and Carbon-Nanotubes Augmented Nickel–Aluminum System

Kinetics and Mechanism of Ignition in Reactive Al/Ni Nanostructured Materials

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