Nucleation and growth of anodic films on stainless steel alloys I. Influence of minor alloying elements and applied potential on passive film growth

1990 ◽  
Vol 20 (2) ◽  
pp. 223-230 ◽  
Author(s):  
H. C. Brookes ◽  
J. W. Bayles ◽  
F. J. Graham
Keyword(s):  
Stainless Steel ◽  
Passive Film ◽  
Film Growth ◽  
Nucleation And Growth ◽  
Alloying Elements ◽  
Applied Potential ◽  
Anodic Films ◽  
Steel Alloys ◽  
Passive Film Growth

Kinetics of Passive Film Growth on 304 Stainless Steel in H2SO4 Pickling Solution under Chemical Oxidation

CORROSION ◽  
10.5006/2680 ◽  
2018 ◽  
Vol 74 (6) ◽  
pp. 705-714 ◽  
Author(s):  
Yingying Yue ◽  
Chengjun Liu ◽  
Edouard Asselin ◽  
Peiyang Shi ◽  
Maofa Jiang
Keyword(s):  
Stainless Steel ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Passive Film ◽  
Polarization Resistance ◽  
Film Growth ◽  
Electrochemical Impedance ◽  
304 Stainless Steel ◽  
Passive Film Growth ◽  
Kinetics Of

H2SO4-H2O2 mixtures are a promising and environmentally friendly passivation medium for the stainless-steel pickling process. The corrosion behavior of stainless steel is highly dependent on the kinetics of passive film growth. Long-term electrochemical measurements, including polarization resistance, open circuit potential (OCP), and electrochemical impedance spectroscopy (EIS) measurements were performed to investigate the evolution of the passive state of 304 stainless steel. According to the OCP results, an active-passive transition takes place in 10 ks in 0.5 M H2SO4 solution containing 0.005 M to 0.3 M H2O2. Polarization resistance results indicate that the passive film thickness keeps growing after OCP stabilization in the presence of H2O2. Electrochemical impedance spectroscopy (EIS) results confirmed that the growth of the passive film in H2SO4-H2O2 solutions takes about 9 h. Additionally, according to the Point Defect Model (PDM) and Mott–Schottky analysis, the semiconductor properties of the passive film on 304 stainless steel in H2SO4-H2O2 solution were studied. The results indicate that the passive film is an n-type semiconductor. The donor density is in the range of 1.6 × 10−21 cm−3 to 24 and decreases exponentially with increasing film formation potential (this potential coincides with the final OCP in the corresponding H2SO4-H2O2 solutions). By postulating that most donors are oxygen vacancies, the point defect properties including diffusivity and electrical field strength are obtained.

Direct evidence of passive film growth on 316 stainless steel in alkaline solution

2017 ◽  
Vol 131 ◽  
pp. 168-174 ◽  
Author(s):  
Bowei Zhang ◽  
Shiji Hao ◽  
Junsheng Wu ◽  
Xiaogang Li ◽  
Chaojiang Li ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Passive Film ◽  
Alkaline Solution ◽  
Direct Evidence ◽  
Film Growth ◽  
316 Stainless Steel ◽  
Passive Film Growth

Kinetics of Passive Film Formation on Scratched Bare Surfaces of Stainless Steels in Magnesium Chloride Solutions

CORROSION ◽  
1993 ◽  
Vol 49 (11) ◽  
pp. 877-884 ◽  
Author(s):  
D. Li ◽  
X. Mao ◽  
R. Zhu
Keyword(s):  
Passive Film ◽  
Stainless Steels ◽  
Magnesium Chloride ◽  
Film Growth ◽  
Strong Electric Field ◽  
Film Formation ◽  
Adsorbed Layer ◽  
Passive Film Growth ◽  
Kinetics Of ◽  
Bare Surface

Abstract Kinetics of passive film formation on the bare surface of scratched stainless steels SS in magnesium chloride (MgCl2) solutions were studied using the rapid scratching technique under potentiostatic conditions. An experimental device was designed to record data at the rate of 20,000 points/s, with the rotating rate of the specimen at 3,000 rpm and a scratch scar length of about 4.6 mm to 4.8 mm. A new phenomenon was observed in that two peaks were seen rather than a continuous decay in the curve of current decay on scratched SS in MgCl2 solutions. Current decayed steeply to approximately passive current within about 2.5 ms to 3 ms after the diamond knife was moved away from the specimen. Current rose again for about 2 ms to 3 ms. This phenomenon was considered to represent the processes of adsorbed layer formation on the bare surface and transformation of the adsorbed layer into a passive film. Results were affected by the recording rate of experimental data, the specimen rotating rate, and the scratch scar length. The kinetics of passive film growth were shown empirically by i(t) = I0exp(−βt) with I0 and β being constants. Passive film growth was controlled by ion conduction in a strong electric field, as defined by i = A exp(BV/x).

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