Surface Structuring of α/β-Sialon Ceramics by Plasma-Etching

Effects of plasma etching on mixed /-sialon ceramics with different /-ratiowere investigated. A mix of CF4/O2 in a ratio of 2:1 was chosen as reactive gas. Parameters such as etching time and the material composition were examined. It was shown that -grains exhibit a larger etching rate than the grain boundary glassy phase or the -grains, generating pockets in a range of few µm. The so created surfaces were characterized both by scanning electron microscopy (SEM) and by atomic force microscopy (AFM) in contact mode. These complementary techniques also enabled the determination of the bearing ratio.

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Determination of Mechanical Properties of Spatially Heterogeneous Breast Tissue Specimens Using Contact Mode Atomic Force Microscopy (AFM)

Annals of Biomedical Engineering ◽

10.1007/s10439-014-1057-x ◽

2014 ◽

Vol 42 (9) ◽

pp. 1806-1822 ◽

Cited By ~ 14

Author(s):

Rajarshi Roy ◽

Jaydev P. Desai

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Breast Tissue ◽

Contact Mode ◽

Force Microscopy ◽

Atomic Force ◽

Tissue Specimens ◽

Mode Atomic Force Microscopy

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Surface roughness measurements of vanadium-contaminated fluidized cracking catalysts by atomic force microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100166798 ◽

1996 ◽

Vol 54 ◽

pp. 866-867

Author(s):

H. Kinney ◽

M.L. Occelli ◽

S.A.C. Gould

Keyword(s):

Surface Roughness ◽

Zeolite Y ◽

Atomic Level ◽

Microporous Structure ◽

Contact Mode ◽

Force Microscopy ◽

Atomic Force ◽

Before And After ◽

Roughness Measurements ◽

Cracking Catalysts

For this study we have used a contact mode atomic force microscope (AFM) to study to topography of fluidized cracking catalysts (FCC), before and after contamination with 5% vanadium. We selected the AFM because of its ability to well characterize the surface roughness of materials down to the atomic level. It is believed that the cracking in the FCCs occurs mainly on the catalysts top 10-15 μm suggesting that the surface corrugation could play a key role in the FCCs microactivity properties. To test this hypothesis, we chose vanadium as a contaminate because this metal is capable of irreversibly destroying the FCC crystallinity as well as it microporous structure. In addition, we wanted to examine the extent to which steaming affects the vanadium contaminated FCC. Using the AFM, we measured the surface roughness of FCCs, before and after contamination and after steaming.We obtained our FCC (GRZ-1) from Davison. The FCC is generated so that it contains and estimated 35% rare earth exchaged zeolite Y, 50% kaolin and 15% binder.

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Dynamic friction energy dissipation and enhanced contrast in high frequency bimodal atomic force microscopy

Friction ◽

10.1007/s40544-021-0489-1 ◽

2021 ◽

Author(s):

Xinfeng Tan ◽

Dan Guo ◽

Jianbin Luo

Keyword(s):

Atomic Force Microscopy ◽

Energy Dissipation ◽

Contact Friction ◽

Measuring Instruments ◽

Dynamic Friction ◽

Contact Mode ◽

Force Microscopy ◽

Atomic Force ◽

Friction Energy ◽

New Applications

AbstractDynamic friction occurs not only between two contact objects sliding against each other, but also between two relative sliding surfaces several nanometres apart. Many emerging micro- and nano-mechanical systems that promise new applications in sensors or information technology may suffer or benefit from noncontact friction. Herein we demonstrate the distance-dependent friction energy dissipation between the tip and the heterogeneous polymers by the bimodal atomic force microscopy (AFM) method driving the second order flexural and the first order torsional vibration simultaneously. The pull-in problem caused by the attractive force is avoided, and the friction dissipation can be imaged near the surface. The friction dissipation coefficient concept is proposed and three different contact states are determined from phase and energy dissipation curves. Image contrast is enhanced in the intermediate setpoint region. The work offers an effective method for directly detecting the friction dissipation and high resolution images, which overcomes the disadvantages of existing methods such as contact mode AFM or other contact friction and wear measuring instruments.

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Atomic force microscopy comparative analysis of the surface roughness of two posterior chamber phakic intraocular lens models: ICL versus IPCL

BMC Ophthalmology ◽

10.1186/s12886-021-02039-6 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Juan Gros-Otero ◽

Samira Ketabi ◽

Rafael Cañones-Zafra ◽

Montserrat Garcia-Gonzalez ◽

Cesar Villa-Collar ◽

...

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Intraocular Lenses ◽

Posterior Chamber ◽

Anterior Surface ◽

Contact Mode ◽

Force Microscopy ◽

Atomic Force ◽

Phakic Intraocular Lenses ◽

Roughness Measurements

Abstract Background To compare the anterior surface roughness of two commercially available posterior chamber phakic intraocular lenses (IOLs) using atomic force microscopy (AFM). Methods Four phakic IOLs were used for this prospective, experimental study: two Visian ICL EVO+ V5 lenses and two iPCL 2.0 lenses. All of them were brand new, were not previously implanted in humans, were monofocal and had a dioptric power of − 12 diopters (D). The anterior surface roughness was assessed using a JPK NanoWizard II® atomic force microscope in contact mode immersed in liquid. Olympus OMCL-RC800PSA commercial silicon nitride cantilever tips were used. Anterior surface roughness measurements were made in 7 areas of 10 × 10 μm at 512 × 512 point resolution. The roughness was measured using the root-mean-square (RMS) value within the given regions. Results The mean of all anterior surface roughness measurements was 6.09 ± 1.33 nm (nm) in the Visian ICL EVO+ V5 and 3.49 ± 0.41 nm in the iPCL 2.0 (p = 0.001). Conclusion In the current study, we found a statistically significant smoother anterior surface in the iPCL 2.0 phakic intraocular lenses compared with the VISIAN ICL EVO+ V5 lenses when studied with atomic force microscopy.

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