Microprobe (EPMA)
Electron Probe Micro Analyser - for highly accurate element analysis.
The technique: Electrons in – x-rays out
In a microprobe the sample is bombarded with a finely focused electron beam. The emitted x-rays are analysed quantitatively or qualitatively using Wavelenght Dispersive Spectroscopy (WDS) and / or Energy Dispersive Spectroscopy (EDS). WDS gives much better energy resolution than EDS and is what makes the microprobe superior to an ordinary SEM when it comes to element analysis.
Some of the uses are: Excact analysis of small volumes, chemical quantification of intermetallic phases, and mapping of inhomogeneities and impurities in cast alloys.
Technical data:
|
Typical analysis volume |
2 µm3 |
|
Lateral resolution |
0.5 – 1 µm |
|
Element analysis |
Beryllium (atomic number 4) and higher |
|
Detection limit |
0.01 weight percent (for most elements) |
Sample requirements:
|
Surface |
Reasonably planar sample |
|
Maximum size |
40 mm x 50 mm x 20 mm
(Standard diameters for polished metallographical samples are 1" and 1 1/4". Depth < 20 mm) |
The microprobe in Trondheim is localised at NTNU.
Contact person:
Trondheim: Morten Raanes, tlf. +47 93059421
