A novel use of rf-GD sputtering for sample surface preparation for SEM: its impact on surface analysis

An infrared interferometer capable of performing real-time full-field noncontacting deformation field measurements on optically rough surfaces is proposed as a tool for elastoplastic fracture mechanics investigations. The choice of the infrared wavelength allows interferometric measurements on fracture samples with little or no surface preparation and is more tolerant of the damage accumulation near the crack. The interferometer also bridges a sensitivity gap among existing techniques for out-of-plane deformation measurement. First, a rigorous Fourier optics analysis is provided for the interferometer and the range of surface roughness that can be studied using this interferometer is examined. The interferometer is then used for mapping deformations near elastoplastically deformed cracks in aluminum beams and solder-copper bimaterials. The regions of dominant three-dimensional effects and J-dominance are examined on the sample surface by evaluating measurements along with companion finite element analyses and the HRR fields.

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AFM-in-SEM as a Tool for Comprehensive Sample Surface Analysis

Microscopy Today ◽

10.1017/s1551929520000875 ◽

2020 ◽

Vol 28 (3) ◽

pp. 38-46

Author(s):

Veronika Novotna ◽

Josef Horak ◽

Martin Konecny ◽

Veronika Hegrova ◽

Ondrej Novotny ◽

...

Keyword(s):

Surface Analysis ◽

Sample Surface ◽

Image Position

Abstract

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Rock Sample Surface Preparation Influences Thermal Infrared Spectra

10.20944/preprints201810.0376.v1 ◽

2018 ◽

Author(s):

Evelien Rost ◽

Christoph Hecker ◽

Martin C. Schodlok ◽

Freek D. van der Meer

Keyword(s):

Surface Roughness ◽

Rock Sample ◽

Surface Preparation ◽

Thermal Infrared ◽

Sample Surface ◽

Spectral Shape ◽

Spectral Signature ◽

Rock Surface ◽

Spectral Signatures ◽

Spectral Contrast

High-resolution laboratory-based thermal infrared spectroscopy is an up-and-coming tool in the field of geological remote sensing. Its spatial resolution allows for detailed analyses at centimeter to sub-millimeter scale. However, this increase in resolution creates challenges with sample characteristics such as grain size, surface roughness and porosity that can influence the spectral signature. This research explores the effect of rock sample surface preparation on the TIR spectral signatures. We applied three surface preparation methods (split, saw and polish) to determine how the resulting differences in surface roughness affects both the spectral shape as well as the spectral contrast. The selected samples are a pure quartz sandstone, a quartz sandstone containing a small percentage of kaolinite, and an intermediate-grained gabbro. To avoid instrument or measurement type biases we conducted measurements on three TIR instruments, resulting in directional hemispherical reflectance spectra, emissivity spectra and bi-directional reflectance images. Surface imaging and analyses were performed with scanning electron microscopy and profilometer measurements. We demonstrate that surface preparation affects the TIR spectral signatures influencing both the spectral contrast as well as the spectral shape. The results show that polished surfaces predominantly display a high spectral contrast while the sawed and split surfaces display up to 25% lower reflectance values. Furthermore, the sawed and split surfaces display spectral signature shape differences at specific wavelengths, which we link to mineral transmission features, surface orientation effects and multiple reflections in fine-grained minerals. Hence, the influence of rock surface preparation should be taken in consideration to avoid an inaccurate geological interpretation.

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Application Example 26: Sample Surface Preparation Using rf-GD Sputtering for Cross-Sectional Examination

New Horizons of Applied Scanning Electron Microscopy - Springer Series in Surface Sciences ◽

10.1007/978-3-642-03160-1_27 ◽

2009 ◽

pp. 105-107

Author(s):

Kenichi Shimizu ◽

Tomoaki Mitani

Keyword(s):

Surface Preparation ◽

Sample Surface ◽

Cross Sectional

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Comparison of the effect of the feldspathic sample surface preparation method on the strength of the bond with orthodontic aesthetic brackets

Forum Ortodontyczne ◽

10.5604/01.3001.0012.7219 ◽

2018 ◽

Vol 14 (3) ◽

pp. 167-177

Author(s):

Olga Włodarczyk-Górniak ◽

Agata Szczesio ◽

Joanna Nowak ◽

Leszek Klimek ◽

Joanna Szczepańska ◽

...

Keyword(s):

Bonding Strength ◽

Preparation Method ◽

Testing Machine ◽

Surface Preparation ◽

Sample Surface ◽

Shear Resistance ◽

Resistance Test ◽

Cohesive Fracture ◽

Orthodontic Bracket ◽

Roughness Profile

As the amount of orthodontically treated adults is steadily increasing, the need arose of adhesive cementation of brackets for crowns and other ceramic restorations. The surface of dentist porcelain does not undergo etching with phosphoric acid (H3PO4) and requires a different procedure protocol. Aim. The aim of the research was to evaluate the strength of the polycrystalline bracket bonds with feldspathic ceramics processed using some selected methods. Material and methods. Feldspathic ceramic samples fired onto a metal cylinder were divided into five groups and processed with the selected methods. The surface was subjected to scanning electron microscope (SEM) imaging and roughness profile examination. Next, after cementing the polycrystalline brackets and after conducting a thermocycling process (24h, 1450 cycles), a technical shear resistance test was performed in a strength testing machine. The resulting adhesive-cohesive fracture was evaluated as well as the ARI (Adhesive Remnant Index). The findings were subjected to statistical analysis. Results. All the samples tested demonstrated that the orthodontic bracket bonding strength with ceramics examined using the shear resistance test amounted to more than 7 MPa, with such bonding strength being considered sufficient to conduct orthodontic treatment. The highest mean strength was obtained and the most frequent adhesive-cohesive fracture with damage to the ceramics was observed in group HF (12,85 MPa). The preparation applied in group MEP (10,03 MPa) had the lowest influence on the ceramics structure. This was observed in the roughness profile test and in the SEM test. The surface structure of the samples in the MEP group did not significantly differ from that in the K group. Conclusions. The tests demonstrated that the alternative procedure methods applied during the feldspathic ceramics surface preparation for adhesive cementing comply with the requirements set by the contemporary orthodontics. (Włodarczyk-Górniak O, Szczesio A, Nowak J, Klimek L, Szczepańska J, Pawłowska E. Comparison of the effect of the feldspathic sample surface preparation method on the strength of the bond with orthodontic aesthetic brackets. Orthod Forum 2018; 14: 167-77).

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On the Methodology of Thermal Desorption Spectroscopy to Evaluate Hydrogen Embrittlement

Materials Science Forum ◽

10.4028/www.scientific.net/msf.706-709.2354 ◽

2012 ◽

Vol 706-709 ◽

pp. 2354-2359 ◽

Cited By ~ 5

Author(s):

Diana Pérez Escobar ◽

Kim Verbeken ◽

Lode Duprez ◽

Marc Verhaege

Keyword(s):

Hydrogen Embrittlement ◽

Thermal Desorption ◽

Surface Preparation ◽

Thermal Desorption Spectroscopy ◽

Sample Surface ◽

Hydrogen Desorption ◽

Sample Geometry ◽

Metal Interactions ◽

Charging Time ◽

The Impact

Thermal desorption spectroscopy (TDS) is a very important tool in hydrogen embrittlement (HE) related research and has been applied on many different materials over the last decades in order to improve knowledge on the HE phenomenon. TDS provides the opportunity to distinguish between different types of hydrogen traps based on the analysis of a spectrum with different peak temperatures each corresponding to hydrogen desorption from a specific trap. These peak temperatures, and consequently the different traps in a material, arise from the various microstructural characteristics of the material. However, TDS results are also influenced by many other parameters, such as the sample surface preparation, the electrolytes used for hydrogen charging, sample geometry, charging time, current density, charging temperature. Even though the use of thermal desorption to evaluate hydrogen-metal interactions has increased over the past years, a careful evaluation of the effect of these other parameters was not yet performed. In this work, the impact of some of the above mentioned parameters was studied. It was demonstrated that the sample geometry, the surface roughness, and the initial total pressure of the TDS chamber influenced significantly the obtained TDS spectrum.

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