Anodic dissolution of chromium at high current densities in sodium nitrate electrolyte

Schneider, Michael; Šimůnková, L.; Mańko, Maria; Lohrengel, M. M.; Hoogsteen, W.

doi:10.1007/s10008-018-4140-7

Cited by 11 publications

(10 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One could expect that the hardest materials like Cr or W will suit the best for the electrodes, however, it is definitely not the case. Chromium is going very fast (in seconds) to the solution because of anodic dissolution 43 . The dissolution occurs also for W 44 but at a lower rate.…”

Section: Resultsmentioning

confidence: 99%

Nanoreactors in action for a durable microactuator using spontaneous combustion of gases in nanobubbles

Uvarov

Svetovoy

2022

Sci Rep

View full text Add to dashboard Cite

A number of recent studies report enhancement of chemical reactions on water microdroplets or inside nanobubbles in water. This finding promises exciting applications, although the mechanism of the reaction acceleration is still not clear. Specifically, the spontaneous combustion of hydrogen and oxygen in nanobubbles opens the way to fabricate truly microscopic engines. An example is an electrochemical membrane actuator with all three dimensions in the micrometer range. The actuator is driven by short voltage pulses of alternating polarity, which generate only nanobubbles. The device operation is, however, restricted by a fast degradation of the electrodes related to a high current density. Here it is demonstrated that the actuator with ruthenium electrodes does not show signs of degradation in the long-term operation. It is the only material able to withstand the extreme conditions of the alternating polarity electrolysis. This property is due to combination of a high mechanical hardness and metallic conductivity of ruthenium oxide. The actuator combines two features considered impossible: on-water catalysis and combustion in a microscopic volume. It provides an exceptional opportunity to drive autonomous microdevices especially for medical or biological applications.

show abstract

Section: Resultsmentioning

confidence: 99%

Nanoreactors in action for a durable microactuator using spontaneous combustion of gases in nanobubbles

Uvarov

Svetovoy

2022

Sci Rep

View full text Add to dashboard Cite

show abstract

“…Firstly, France and Greene, [ 37 ] Hamm et al, [ 38 ] and Ruel et al [ 39 ] proposed, based on investigations on stainless steel in sulfuric acid, that the increase in current density is due to the dissolution of alloying elements such as chromium, nickel, and molybdenum. Schneider et al [ 40 ] and Harst [ 27 ] focused on potentiodynamic measurements of chromium, manganese, and molybdenum in sodium nitrate solution, which is more relevant for this study. It was shown that all elements are transpassive at the secondary passivation potential of ground 42CrMo4.…”

Section: Discussionmentioning

confidence: 99%

Impact of rim zone modifications on the surface finishing of ferritic–pearlitic 42CrMo4 using electrochemical machining

Zander

Schupp

Mergenthaler

et al. 2021

Materials & Corrosion

View full text Add to dashboard Cite

The efficiency of material removal using electrochemical machining (ECM) is highly dependent on the initial rim zone modifications of the material to be processed. The influence of the rim zone modifications, such as topography and microstructure, on ECM, is investigated on ferritic–pearlitic 42CrMo4 steel by experiment and simulation. 42CrMo4 steel in two different premachining states—ground and electric discharge machined (EDM)—is subjected to a subsequent surface finishing by ECM in sodium nitrate solution. Before and after ECM, the topography and microstructure are examined using scanning electron microscopy, X‐ray diffractometer, and topography analysis methods. The electrochemical properties of the material are determined by potentiodynamic polarization. The efficiency of surface finishing by ECM is quantified by mass spectroscopic analysis (inductively coupled plasma mass spectrometry) of the process electrolyte and related to the rim zone modifications by simulation. The results reveal that the efficiency of material removal during ECM is higher for EDM than for ground 42CrMo4. This is attributed to an increased roughness of EDM 42CrMo4 and to the unfavorable electrochemical properties of the cementite phase in ground 42CrMo4.

show abstract

“…45% of the anode current used to release oxygen. With the increase of the applied potential, the valence of chromium dissolution decreased to z = 3.5 [15].…”

Section: Dissolution Of Stainless Steel In Sodium Chloride Solution At Polarization By Non-stationary Currentmentioning

confidence: 95%

“…The electrochemical dissolution behavior of pure iron and chromium metals were studied in various aqueous media [13][14][15]. The anodic dissolution of iron in H2SO4 and HNO3 solutions was studied with a Pt electrode modified with polyaniline by using SECM.…”

Section: Dissolution Of Stainless Steel In Sodium Chloride Solution At Polarization By Non-stationary Currentmentioning

confidence: 99%

Dissolution of Stainless Steel in Sodium Chloride Solution at Polarization by Non-Stationary Current

Nurdillayeva¹,

Sauirbay²,

Bayeshov³

2021

News of NAN RK. SCTS

View full text Add to dashboard Cite

Stainless steel is in great demand due to its mechanical strength, heat resistance, and resistance to corrosive environments. This article presents the result of a study of the electrochemical dissolution behavior of a stainless steel electrode (12X18H10T) at polarization by 50 Hz alternating current in a neutral medium (NaCl). Preliminary experiments have shown that the main processes do not take place when two stainless steel electrodes are polarized with an alternating current. It was observed that by the polarization of the “stainless steel – titanium” pair electrodes with alternating current, the alloy is intensively dissolved with the formation of iron (II) and chromium (III) ions. This is due to the "valve" properties of the oxide layer formed on the surface of the titanium electrode. A change in the value of the current density of the titanium and steel electrodes significantly affects the process of electrochemical dissolution of the alloy. At high current densities, the dissolution rate of the alloy decreases due to the deterioration of the current correcting properties of titanium. With an increase in the electrolyte concentration, the current efficiency is reduced as salt passivation occurs. A maximum value of the current efficiency of dissolution of stainless steel was observed at a current frequency of 50 Hz. High frequencies of the alternating current do not provide an adjustable duration of the anodic half-cycle for the oxidation reaction due to the frequent change of halfcycles of the alternating current. It was observed that increasing the temperature of the electrolyte reduces the current efficiency of the electrochemical dissolution of stainless steel electrodes. The effects of main electrochemical parameters on the electrolysis process have been investigated, and the optimal conditions of the alloy dissolution were established (іТі = 60 kA/m2 , іSS = 800 A/m2 , [NaCl] = 2.0 M, t = 30, ν = 50 Hz.).

show abstract

Anodic dissolution of chromium at high current densities in sodium nitrate electrolyte

Cited by 11 publications

References 14 publications

Nanoreactors in action for a durable microactuator using spontaneous combustion of gases in nanobubbles

Nanoreactors in action for a durable microactuator using spontaneous combustion of gases in nanobubbles

Impact of rim zone modifications on the surface finishing of ferritic–pearlitic 42CrMo4 using electrochemical machining

Dissolution of Stainless Steel in Sodium Chloride Solution at Polarization by Non-Stationary Current

Contact Info

Product

Resources

About