Integrated Preparation and Imaging Techniques for the Microstructural and Geochemical Characterization of Shale by Scanning Electron Microscopy October 20, 2020 Applications, Sample Preparation 0 To better understand the influence of microscale geochemical and microstructural relationships on the bulk petrophysical properties of unconventional shale systems, core samples from four producing North American formations were cross-sectioned with an argon ion polisher and imaged with a field emission scanning electron microscope (FE-SEM) using a variety of complementary detectors. We demonstrate distinct advantages of the ion-polishing technique for the preservation of the internal shale structure. Moreover, we show how such preparation affords a wider choice of imaging options for both chemical and structural characterization, such as backscatter electron observation at varying beam potentials coupled with x-ray and cathodoluminescence spectroscopic techniques. For full details: Attached files often contain the full content of the item you are viewing. Be sure and view any attachments. AAPG Chapter Shale Characterization.pdf 2.12 MB Related Articles Direct Scanning Electron Microscopy Imaging of Ferroelectric Domains After Ion Milling A method for directly observing the ferroelectric domain structure by scanning electron microscopy after argon ion milling has been established. Its advantages are exemplified by exposing the domain structure in three widely used ferroelectric ceramics, BaTiO3, (Na,K)NbO3, and Pb(Ti,Zr)O3. Stable high-resolution images revealing domains with widths <30 nm have been obtained. The domain contrast is caused by electron channeling and is strongly dependent on the sample tilt angle. Owing to a strain- and defect-free surface generated by gentle ion milling, pronounced orientation contrast is observed. Designing Better Batteries Through Innovative Microscopy Characterization Scanning Electron Microscopes (SEM) support the development of new LIB technologies with morphological observation at the micrometer to nanometer scale, as well as the chemical analysis needed to create high-performance coatings and powders. Ultra-low voltage imaging combined with signal filtering in the SEM allows direct imaging and analysis of battery constituents (anode and cathode) with nanometer resolution. Additionally, one of the important aspects of the analysis is the ability to probe chemistry of the constituents at nm scale (Fig. 1). JEOL FESEM offers the ability to perform microanalysis with energy dispersive spectroscopy (EDS) at extremely low voltages to pinpoint localized makeup of the specimens and, in particular, low atomic number materials such as carbon and fluorine. Moreover, the unique JEOL Soft X-ray spectrometer (SXES) allows researchers to analyze Li. New Cross-Section Sample Preparation Method Applied to Microstructural and Chemical Investigation of Steel Coatings using FE-SEM Steel strips coated with Al-43.5Zn-1.5Si (Galvalume) alloy exhibit superior corrosion resistance as compared to Zn galvanized steel strips. The continuous hot-dip coating process used to produce such coatings entails a metallurgical reaction between the steel strip and Al-Zn-Si liquid alloy that leads to formation of an intermetallic compound layer at the steel-coating interface. Formability of the coated strip depends strongly on the morphology, dimensions (thickness) and chemical nature of this intermetallic layer. Proper characterization of the intermetallic layer structure and chemistry and the nucleation sites on the steel surface is therefore of paramount importance for the development of formable Galvalume coated steel strips. This requires preparation of artifact free cross-sectional samples. Such samples can be obtained using JEOL Cross-section Polisher (CP). Unlike mechanical sample preparation techniques that introduce significant amount of strain and possible artifacts due to preferential etching of various constituents, the CP uses a broad Ar beam and a rocking stage that minimize possible preferential etching and produces strain free cross-sections. In this paper, SEM images as well as chemical (EDS) data characterizing the interface layer between the steel strip and the Galvalume coating prepared using Cross-sectional Polisher are presented. Imaging Texture and Porosity in Mudstones and Shales: Comparison of Secondary and Ion-Milled Backscatter SEM Methods Observations from a number of unconventional reservoirs lead us to conclude that four major pore types exist in fine-grained reservoir and non-reservoir rocks, that they are effectively connected, and that pore sizes from nanometers to microns must be considered when evaluating size distributions. This paper uses SEM imaging of Haynesville, Horn River, Barnett and Marcellus Shales to illustrate that pore types other than those hosted by organics are present in unconventional shale gas reservoirs, and that they are continuous and connected to kerogen-hosted pores. In addition, we present evidence that the maximum size of pores originating in organic matter is determined by the size of the kerogen mass (in the case of organic particles) or the geometry of enclosing crystals (in the case of amorphous, pore-filling kerogen). Pairs of secondary and ion-milled backscatter SEM images address the misconception that large pores observed in secondary electron images are grain pullouts. Pristine Sample Preparation Using Broad Ion Beam Traditional mechanical preparation of specimen surfaces suffers from various artifacts, such as scratches and embedded polishing media, that obscure the original microstructure, crystallographic information and precise layer thickness measurements. Broad ion beam polishing using the JEOL cross-section polisher (CP) offers pristine surface preparation with minimal artifacts. CP is a tabletop instrument that is ideally suited for preparation of a variety of environmentally-sensitive and beam-sensitive materials, including metals, polymers, ceramics and composites. The instrument includes both cryo-preparation (down to LN2temperature) and air-isolated transfer and preparation environment. Cross Section Specimen Preparation Device Using Argon Ion Beam for SEM Scanning Electron Microscopes (SEMs) have been used for various applications, such as research and development and failure analysis. There are many cases where not only observation of a specimen surface – but also observation of a cross section – is important. Preparation of a cross section depends on the specimen structure, observation purpose, and materials. Various preparation methods are put into practice: cutting, mechanical polishing, microtome, and FIB (Focused Ion Beam) are the major methods. In this discussion, we evaluate a new cross section specimen preparation method using an argon ion beam (hereinafter called the Cross-section Polishing or CP method). We have found that this method is extremely useful for observation of layer structures, interfaces, and crystalline structures of metals, ceramics, and composites. Here, we introduce examples of applications to various types of specimens. Showing 0 Comment Comments are closed.