Material analysis: Until the sparks fly

In our vacuum spark emission spectrometer, the sample is excited using high-frequency voltage. The emitted light is then analyzed inside the device and evaluated in the software for the chemical elements detected and their mass fractions.

For material analysis, it is usually necessary to prepare the test surfaces of the sample before testing. The test surface is roughly ground with silicon carbide abrasive paper, thoroughly cleaned under running water and then dried without leaving any residue. This ensures reliable results.

For the test, the sample is placed between two electrodes including an air gap to the counter electrode. The test space under the sample is flooded with argon to avoid falsification of results due to the influence of oxygen. The sample is then excited locally using a high-frequency voltage. At the transition of the electrical voltage on the sample surface, a small part of the test surface is vaporized and brought into the state of a light-emitting plasma. The different wavelengths of light are then analyzed and evaluated in the device. The result is a table showing the chemical composition of the metal with mass fractions of the alloying elements. This data can then be compared with the standardized composition of the target material, for example.