An empirical analysis of nitrogen pressure effect on grain size development of nanostructured ternary nitride coatings

An empirical relationship between the grain diameter of ternary nitride coatings and trhe nitrogen deposition pressure was formulated in the present study. A linear relationship was established between the reciprocals of the square roots of the rgain diameter of the coatings and the nitrogen deposition pressure. It was further confirmed that the equation parameter, md of the empirical relationship was linearly proportional to the primary yield of the coating materials. With defined discharge conditions and sputter characteristics of the larget materials, the values of md for diffeent coatings can be calculated and te rgain size of the coating structure at different nitrogen deposition pressures can be determined

Spectral Imaging and X-Ray Microanalysis with Multiple Detectors

We have progressively refined our requirements for high quality x-ray mapping, which has been a process of learning, advancing our hardware and redefining our requirements. Mapping is not a simple `one size fits all scenario. There are still simple applications where dot mapping, especially with a wavelength dispersive spectrometer, can achieve the required results. The good thing about mapping is that there is always something new that can be learned and we are continually pushing back the boundaries of what can be achieved with mapping. It wont be far into the future that we will have an electron microscope specifically set up to do live x-ray imaging, as we now do for electron imaging. The biggest problem we face is one of being able to determine the level of sophistication in our treatment of the data collected. As with automatic peak identification and standardless analysis it is very easy to produce bad results [1]. The good news is that if you are prepared to set your system up for high quality standards analysis, then most of these problems disappear

High temperature behaviour of magnetron sputtered nanocrystalline titanium aluminium nitride coatings

This paper is to study the thermal stability of nanocrystalline ternary nitride coatings at elevated temperatures. Nanocrystalline titanium aluminium nitride coatings were produced by reactive magnetron co-sputtering on glass substrates and AISI H13 tool steel substrates with nitrogen pressures of 0.4 and 0.65 mTorr (0.053 and 0.086 Pa) respectively. Heat treatment was applied to the coatings at temperatures up to 1000C. It was found that an unexpected grain refinement occurred in the coatings deposited at 0.4 mTorr nitrogen pressure after the heat treatment. a stronger development of TiN(TiAIN (200) component was also evident at temperatures above 800C. With a finer and densified grain struicture, the hardness of the coatings increased substantially from ~1700 to 2300HV

Characterisation of materials through x-ray mapping

Scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS, wavelength dispersive spectroscopy (WDS) and the conbination of these techniques through x-ray mapping (XRM) have become excellent tool for characterising the distribution of elements and phases in materials. Quantitative x-ray mapping (QXRM) enables reliable quantitative results that cna be an order of magnitude better than traditional analysis and is also far superior to regions of interest x-ray maps(ROIM) where low levels of an element overlaps are present

X-ray mapping and post processing

Characterisation of materials frequently involves the determination of variation in composition, structure and microstructure, by the use of a variety of imaging and analysis techniques. There is an increasing need to understand materials phenomena and processes and to learn more about exploiting subtle changes in the distribution of elements in materials technology. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), wavelength dispersive spectroscopy (WDS) and the combination of these techniques through x-ray mapping (XRM) has become an excellent tool for characterising the distribution of elements and phases in materials. This analytical technique provides a high magnification image related to the distribution and relative abundance of elements within a given specimen and thus makes XRM particularly useful for: • identifying the location of individual elements and • mapping the spatial distribution of specific elements and phases within a sample (material surface). Quantitative x-ray mapping (QXRM) enables reliable quantitative results that can be an order of magnitude better than traditional analysis and is also far superior to regions of interest x-ray maps (ROIM) where low levels of an element or elemental overlaps are present

Multi-detector x-ray mapping and generation of correction factor images for problem solving

X-ray mapping with Silicon Drift detectors (SDD’s) and multi-EDS detector systems has become an invaluable analysis technique because the time to perform an x-ray map is reduced considerably. Live x-ray imaging can now been performed with so much data collected in a matter of minutes. The use of multi-EDS detector systems has made this form of mapping even quicker and has also given users the ability to map minor and trace elements very accurately. How the data is collected and summed with multi-EDS detectors is very critical for accurate quantitative x-ray mapping (QXRM). There is a great deal of further information that can be obtained from x-ray maps. This includes elemental relationship or scatter diagram creation, elemental ratio mapping, chemical phase mapping (CPM) and quantitative x-ray maps. In obtaining quantitative x-ray maps we are able to easily generate atomic number (Z), absorption (A), fluorescence (F), theoretical back scatter coefficient (η) and a quantitative total maps from each pixel in the image. This allows us to generate an image corresponding to each factor (for each element present). These images allow us to predict and verify where we are likely to have problems in our images, and are especially helpful to look at possible interface artefacts

EBSD investigations of Equal Channel Angular Extruded copper

Development of nano- and submicron-structured materials has attracted significant research interest in the last ten years [1, 2]. Most recently, an innovative technology called the Equal Channel Angular Extrusion (ECAE) process has demonstrated its capability of producing nano- and submicronstructured metallic alloys with substantial strength improvement [3-8]. ECAE adopts the principle of mechanical attrition and imposes very heavy shear deformation on bulk materials without causing major dimensional changes of the extruded products [3]. It has been suggested that this technology has great advantages over the conventional mechanical attrition of ball milling because it can produce large sized samples free of any residual porosity

Fabrication of double nano-cup assemblies and their anomalous plasmon absorption

Double-cup assemblies of nanoscale gold semi-shells have been synthesized using a combination of thermal evaporation and chemical etching. The optical extinction of these structures peaked at 740 nm, but there was also evidence of additional extinction maxima at 560, 940 and 1110 nm. Numerical simulations of the optical properties revealed that the extinction was due mainly to scattering rather than to absorption In contrast, the extinction in simple single-shell nanocups was strongly absorptive in nature. Multiple plasmon resonances were identified in the double-cup structures, including an interesting quadrupole resonance in which oscillations of the inner and outer shells should operate 180° out-of-phase. © 2008 IEEE

X-ray mapping and scatter diagram analysis of the discoloring products resulting from the interaction of artist's pigments

The discoloring interaction between the artist's pigments cadmium yellow and the copper-containing malachite, an interaction that is conjectured to cause black spotting in oil paintings of the 19th and early 20th centuries, was examined using X-ray mapping and scatter diagram analysis. The application of these coupled techniques confirmed that copper sulfide phases were produced during discoloration reaction. Scatter diagram analysis indicated that two copper sulfide stoichiometries (CuS and Cu3S2) were present as reaction products where previously only crystalline CuS (covellite) had been identified by X-ray diffraction. The results demonstrate the potential of X-ray mapping coupled with scatter diagram analysis for the identification of both crystalline and X-ray amorphous phases produced by such complex heterogeneous interactions and their applicability to the investigation of interactions of artists' pigments. © Microscopy Society of America 2010