In Situ Nanoscale Characterization of Water Penetration through Plasma Polymerized Coatings

Langmuir ◽  
2018 ◽  
Vol 34 (33) ◽  
pp. 9634-9644 ◽  
Author(s):  
Yang Zhou ◽  
Brian Josey ◽  
Emmanuel Anim-Danso ◽  
Brian Maranville ◽  
Jenia Karapetrova ◽  
...  
1994 ◽  
Vol 376 ◽  
Author(s):  
Sean G. Corcoran ◽  
David Wiesler ◽  
John Barker ◽  
Karl Sieradzki

ABSTRACTIn situ small angle neutron scattering (SANS) was used to characterize the formation of the random 3-dimensional porous structure created during the free corrosion of a Ag0.7Au0.3 alloy in concentrated HNO3. The evolution of the porosity was followed in situ for a period of 21 hours. The average ligament width evolved from a size of approximately 6 nm following only 7 minutes of dealloying to approximately 22.5 nm after 21 hours of de-alloying. Using a model developed by N.F. Berk (Phys. Rev. Lett., 58 (1987) 2718) for the scattering properties of random porous media, we were able to characterize the average ligament width distribution as a function of time. Our results represent the first in situ nanoscale characterization of the formation of 3-dimensional porosity in a corrosion system.


2021 ◽  
Vol 536 ◽  
pp. 147781
Author(s):  
Tuan T. Tran ◽  
Christian Lavoie ◽  
Zhen Zhang ◽  
Daniel Primetzhofer

1996 ◽  
Vol 451 ◽  
Author(s):  
Sean G. Corcoran ◽  
David G. Wiesler ◽  
Karl Sieradzki

ABSTRACTIn situ small angle neutron scattering (SANS) was used to characterize the formation of the random 3-dimensional porous structure created during the dealloying of a Ag0.7Au0.3 alloy under potential control. Using a model developed by N.F. Berk (Phys. Rev. Lett., 58 (1987) 2718) for the scattering properties of random porous media, we were able to characterize the average ligament width as a function of time during the dealloying process. We find that the coarsening of the average ligament width is strongly dependent upon the value of the applied potential. Our results represent the first in situ nanoscale characterization of the 3-dimensional formation of porosity in a dealloying system under potential control.


2013 ◽  
Vol 251 (1) ◽  
pp. 27-34 ◽  
Author(s):  
A. DUTTA ◽  
C.J. CLUKAY ◽  
C.N. GRABILL ◽  
D.J. FREPPON ◽  
A. BHATTACHARYA ◽  
...  

Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
J. I. Bennetch

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.


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