ELECTRON MICROSCOPY SEM-EDX
EDX equipped electron microscopy allows two fundamental analysis:
- Morphological Analysis: it is possible to see a sample at very high magnifications, if compared to optical microscopy, with a very high level of contrast. By using different techniques, for example switching between secondary electrons and backscattered electrons observation, it is possible to see a 3D image of the sample, by intensification of the surface or the bulk components of the observed portions of samples.
- Chemical elements analysis: with EDX you can measure both qualitatively and quantitatively the chemical elements in every point of the sample, pointing on single point, on definite portions or lines, or by mapping chimcally the entire image.
With actual electronic systems, electron microsocopy goes beyond the old difficulties in the sample preparation, and can give better results in very short times.
RDLAB137 is equipped with a new generation instrument: by utilization of specific methods for polimeric based materials, we can analyize complex samples in shorter times, compared with the past.
These opportunities allow us to propose work sessions with the customers, which know their materials better than us: working together in front of the SEM-EDX can give the best results and can solve the requests during the session. Or it can pose the basis for the future observations on specific type of samples.
Here follows a brief list of the potentiality of the technique:
- Sub-micrometric analysis of defects
- Morphological analysis of particles, fibres, dusts, conglomerates; in matrix or isolated.
- Dispersion analysis of particles
- Chemical composition analhysis (chemical elements), with a submicrometrics resolution.
- Mapping analysis of chemical elements
- Dimensional analysis, on single points, or statistical
DIFFERENT CONFIGURATIONS FOR DIFFERENT NEEDS
Secondary electrons, backscattered electrons, Mix observations, EDX, Accelerated Voltages, Charge reduction, Low, Middle, High Magnification..... and other more
First heared question regarding a microscope, electronic or optical, is often: "What is the higher magnification?". Very bad question. The magnification is a parameter, but it is often not important for obtaning the requested results; particularly if we are speaking of plastics or rubber applications.
The image quality and its details, the contrast, the possibility to catch with precision low signals for EDX measurements, these are often more important factors, if compared with the magnification.
Here follows, as example, the same particle observed in 2 different configurations:
It is possible to note that the detail is very different: secondary electrons are often utilized fot topographic investigations and give a good idea of the morphology. Backscattered electrons are utilized for compositional analysis too, because the atomic number of the element targeted from the electron gun modifies the diffusion mechanism; the 'luminosity' of the image points is a function of atomic number.
Very important is the possibility to analyze point with X rays spectroscopy: with our system it is possibile to:
- Measure single points in every part of the sample
- Draw specific parts with desired form and dimension and analyze these parts
- Do a 'line' scansion in every direction
- Map all the image, point by point, in order to have a 'photography' of the distribution of every chemical element in the sample
Here you can find an example of EDX microanalysis of a natural fibre, which in this case has been carried out in the zone selected by the green rectangle:
This is the EDX microanalysis, with which is possible to obtain the relative quantification of the % of the chemical elements:
Many other arrangements of configuration are possible, in order to obtain the best signals and reach the best information of the morphological and chemical composition of samples.