In situ monitoring of the microstructural corrosion mechanisms of zinc–magnesium–aluminium alloys using time lapse microscopy

2011 ◽  
Vol 53 (6) ◽  
pp. 2208-2215 ◽  
Author(s):  
James Sullivan ◽  
Shahin Mehraban ◽  
Jon Elvins
Keyword(s):  
Aluminium Alloys ◽  
Time Lapse ◽  
In Situ Monitoring ◽  
Time Lapse Microscopy ◽  
Corrosion Mechanisms

scholarly journals In situ monitoring of corrosion mechanisms and phosphate inhibitor surface deposition during corrosion of zinc–magnesium–aluminium (ZMA) alloys using novel time-lapse microscopy

2015 ◽  
Vol 180 ◽  
pp. 361-379 ◽  
Author(s):  
James Sullivan ◽  
Nathan Cooze ◽  
Callum Gallagher ◽  
Tom Lewis ◽  
Tomas Prosek ◽  
...  
Keyword(s):  
Image Analysis ◽  
Mass Loss ◽  
Alloy System ◽  
Time Lapse ◽  
Open Circuit ◽  
In Situ Monitoring ◽  
Corrosion Mechanism ◽  
Saturation Effects ◽  
Corrosion Mechanisms

In situtime-lapse optical microscopy was used to examine the microstructural corrosion mechanisms in three zinc–magnesium–aluminium (ZMA) alloy coated steels immersed in 1% NaCl pH 7. Preferential corrosion of MgZn2lamellae within the eutectic phases was observed in all the ZMA alloys followed by subsequent dissolution of Zn rich phases. The total extent and rate of corrosion, measured using time-lapse image analysis and scanning vibrating electrode technique (SVET) estimated mass loss, decreased as Mg and Al alloying additions were increased up to a level of 3 wt% Mg and 3.7 wt% Al. This was probably due to the increased presence of MgO and Al2O3at the alloy surface retarding the kinetics of cathodic oxygen reduction. The addition of 1 × 10−2mol dm−3Na3PO4to 1% NaCl pH 7 had a dramatic influence on the corrosion mechanism for a ZMA with passivation of anodic sites through phosphate precipitation observed using time-lapse image analysis. Intriguing rapid precipitation of filamentous phosphate was also observed and it is postulated that these filaments nucleate and grow due to super saturation effects. Polarisation experiments showed that the addition of 1 × 10−2mol dm−3Na3PO4to the 1% NaCl electrolyte promoted an anodic shift of 50 mV in open circuit potential for the ZMA alloy with a reduction in anodic current of 2.5 orders of magnitude suggesting that it was acting primarily as an anodic inhibitor supporting the inferences from the time-lapse investigations. These phosphate additions resulted in a 98% reduction in estimated mass loss as measured by SVET demonstrating the effectiveness of phosphate inhibitors for this alloy system.

In situ monitoring of single molecule binding reactions with time-lapse atomic force microscopy on functionalized DNA origami

Nanoscale ◽  
2011 ◽  
Vol 3 (6) ◽  
pp. 2481 ◽  
Author(s):  
Na Wu ◽  
Xingfei Zhou ◽  
Daniel M. Czajkowsky ◽  
Ming Ye ◽  
Dongdong Zeng ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Single Molecule ◽  
Time Lapse ◽  
Dna Origami ◽  
In Situ Monitoring ◽  
Force Microscopy ◽  
Atomic Force

scholarly journals Respirometric in Situ Methods for Real-Time Monitoring of Corrosion Rates: Part II. Immersion

2020 ◽  
Author(s):  
Michael Strebl ◽  
Mark Bruns ◽  
Ghina Schulze ◽  
Sannakaisa Virtanen
Keyword(s):  
Real Time ◽  
In Situ Monitoring ◽  
Intermittent Flow ◽  
Real Time Monitoring ◽  
Corrosion Rates ◽  
Immersion Corrosion ◽  
In Situ Methods ◽  
Flow Through ◽  
Corrosion Mechanisms

With the aim to open a new window into corrosion processes this paper presents respirometric methods for real-time in situ monitoring of corrosion rates under immersion conditions. With these techniques, sensitive, non-destructive corrosion rate measurements are possible on basically all metals and alloys. Different methods are presented that enable to monitor HER, ORR or both reactions simultaneously based on the amount of evolved H2 or the amount of consumed O2 by volumetric, manometric and sensor-based approaches. Various research examples are presented, demonstrating the benefits and limitations of the different approaches. For Mg alloys, besides HER, ORR plays a role in the cathodic reactions and a good correlation of the total cathodic charge with mass loss was obtained. H2 dissolution into the electrolyte was identified as an important factor. The results obtained for Zn immersion corrosion in intermittent-flow and flow-through respirometric experiments suggest that the ORR mechanism leads to the generation of stable H2O2 under these conditions. As a result, the effective number of exchanged electrons for one O2 molecule was found to be in between two and four. The here introduced respirometric techniques allow new insights into corrosion mechanisms, in addition to enabling real-time monitoring of corrosion.

The piezoelectric implant: its applications to the in situ monitoring of materials

2001 ◽  
Vol 89 ◽  
pp. 24-26
Author(s):  
Y. Jayet ◽  
J.-C. Baboux
Keyword(s):  
In Situ Monitoring

Fetal pulse oximeter for in situ monitoring during labour and birth

2008 ◽  
Vol 52 (1-2) ◽  
pp. 85
Author(s):  
Ákos Becker ◽  
Gábor Harsányi
Keyword(s):  
Pulse Oximeter ◽  
In Situ Monitoring
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