Towards a better understanding of the oxide film growth mechanism in E110 zirconium alloy under high-temperature oxidation in steam

2020 ◽  
Vol 38 (2) ◽  
pp. 165-181
Author(s):  
Andrey B. Rozhnov ◽  
Hannanh Alsheikh ◽  
Sergey A. Nikulin ◽  
Vladislav A. Belov ◽  
Elina V. Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Oxide Film ◽  
Zirconium Alloy ◽  
High Temperature Oxidation ◽  
Film Growth ◽  
Surface Oxide Film ◽  
Temperature Oxidation ◽  
Interface Growth ◽  
White Spots ◽  
Alloy Oxidation

AbstractHigh-temperature oxidation of E110 (Zr-1%Nb) zirconium alloy in steam at Т = 1100°C to various degrees has been carried out. Based on the studies of morphology and microstructure of the oxide film and metal, as well as on review of previously published results, the mechanism of alloy oxidation has been proposed, which includes oxide thickening close to the oxide/metal interface, growth of the thickened areas and their conversion into nodules, growth of the nodules and crowning of the metal surface (white spots), clustering of nodules under the formed oxide, formation of a double (white on the surface) oxide film and delamination of the oxide upper layer.

High-Temperature Oxidation Behaviors of 30Cr25Ni20Si Heat-Resistant Steel in Air

2020 ◽  
Vol 861 ◽  
pp. 83-88
Author(s):  
You Yang ◽  
Xiao Dong Wang
Keyword(s):  
High Temperature ◽  
Oxide Film ◽  
High Temperature Oxidation ◽  
Film Growth ◽  
Surface Oxidation ◽  
Mass Gain ◽  
Resistant Steel ◽  
Temperature Oxidation ◽  
Heat Resistant Steel ◽  
Heat Resistant

High temperature oxidation dynamic behaviors and mechanisms for 30Cr25Ni20Si heat-resistant steel were investigated at 800, 900 and 1000°C. The oxide layers were characterized by scanning electron microscopy (SEM-EDS), X-ray diffractometer (XRD). The results showed that the oxidation rate of test alloys is increased with increasing the oxidation time. The oxidation dynamic curves at 800 and 900°C follow from liner to parabolic oxidation law. The transition point is 10 h. At 1000°C, the steel exhibits a catastrophic oxidation, and the oxidation mass gain value at 50 h is 0.77 mg/cm2. This suggests that the steel at 900°C has formed a dense protective surface oxidation film, effectively preventing the diffusion of the oxygen atoms and other corrosive gas into the alloy. Therefore, at the first stage of oxidation, chemical adsorption and reaction determine the oxide film composition and formation process. At the oxide film growth stage, oxidation is controlled by migration of ions or electrons across the oxide film. When the spinel scale forms, it acts as a compact barrier for O element and improving the oxidation resistance.

scholarly journals The high temperature oxidation of metals

1926 ◽  
Vol 111 (757) ◽  
pp. 203-209 ◽  
Keyword(s):  
High Temperature ◽  
Oxide Film ◽  
High Temperature Oxidation ◽  
Protective Action ◽  
Protective Film ◽  
Parent Metal ◽  
Compact Structure ◽  
Temperature Oxidation ◽  
Protective Properties ◽  
Porous Oxide

The oxidation of metals at high temperatures has been investigated with some thoroughness by Pilling and Bedworth. They found that the metals could be divided into two great classes according to the nature of the oxide produced. If the volume of the oxide is greater than that of the metal from which it was produced an oxide film of compact structure and protective properties will be produced. If the volume of the oxide is less than that of its parent metal a porous oxide is produced which has no protective action whatever. The oxidation of the metals of the first class is controlled by the diffusion of oxygen through the protective film of oxide and the application of the diffusion laws to this process lead us to expect that the oxidation law will be W 2 = K t W 2 = amount of oxygen absorbed t = time K is a constant.

Influence of the Third Element on the High Temperature Oxidation Behavior of γ'-Ni3Al Alloys

2006 ◽  
Vol 522-523 ◽  
pp. 617-624 ◽  
Author(s):  
Shinya Mikuni ◽  
Shigenari Hayashi ◽  
Toshio Narita
Keyword(s):  
High Temperature ◽  
High Temperature Oxidation ◽  
Oxidation Behavior ◽  
Al Alloys ◽  
Temperature Oxidation ◽  
The Third ◽  
Alloy Oxidation ◽  
Oxidation Performance ◽  
Fe Alloys ◽  
High Temperature Oxidation Behavior

The effects of the third element on the high temperature oxidation of γ'-Ni3Al with 5at%X (X=Ti, Ta, Nb, Cu, Co and Fe) alloys were investigated at 1173K in air, and oxidation behavior could be classified into three groups. The first group, comprised of alloys with Cu and Co, showed good oxidation performance with Al2O3 formation. A second group contains Ti, Ta, and Nb as alloying elements, and showed poor oxidation performance. With Fe or Mn addition the alloy oxidation performance was intermediate between the first and second group. The effects of these elements are discussed associate with partitioning factors for each element in the γ'-phase.

scholarly journals In-situ time-resolved study of structural evolutions in a zirconium alloy during high temperature oxidation and cooling

2019 ◽  
Vol 158 ◽  
pp. 109971 ◽  
Author(s):  
R. Guillou ◽  
M. Le Saux ◽  
E. Rouesne ◽  
D. Hamon ◽  
C. Toffolon-Masclet ◽  
...  
Keyword(s):  
High Temperature ◽  
Zirconium Alloy ◽  
High Temperature Oxidation ◽  
Time Resolved ◽  
Temperature Oxidation

On the problems of creating shells of fuel rods from zirconium alloys for tolerant fuel

2021 ◽  
Vol 3 ◽  
pp. 69-78
Author(s):  
A. A. Yakushkin ◽  
Keyword(s):  
High Temperature ◽  
Production Technology ◽  
Zirconium Alloy ◽  
High Temperature Oxidation ◽  
Fuel Cladding ◽  
Temperature Oxidation ◽  
Corrosion Resistant ◽  
Fuel Rod ◽  
Kinetics Of ◽  
Corrosion Resistant Coating

Three directions of the establishment of accident tolerant fuel cladding for light water reactors are actively exploring at present: 1) replacement zirconium alloy E110 for more corrosion-resistant material in accident operation conditions; 2) surface dispersion hardening or doping of the zirconium cladding of fuel element; 3) deposition a corrosion-resistant coating to the fuel cladding. The first direction requires significant and irreversible changes in fuel rod production technology and has long-term prospects. Conversely, the second direction suggest minimal changes in the fuel rod production technology, however, it has no significant effect on the high temperature oxidation kinetics of fuel claddings in steam. Using of a corrosion resistant coating results in a significant change in the high temperature oxidation kinetics of the zirconium alloy, (no transition to linear oxidation) that is related to maintaining the continuity of the oxide layer formed during oxidation. The issue provides a brief overview of the current state of research in the field of fuel, tolerant to the effects of coolant in emergency situations.

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