Chemical analysis / Optical emission spectroscopy (OES)

This test method, also called spark spectrometry, is used to determine the chemical composition of metallic materials (non-ferrous metals, iron and steel materials, cobalt, nickel, titanium alloys). The method is partially destructive. 

The surface is "sparked off" (the material is vaporised in the arc) and the emitted spectral lines are analysed. This allows the respective chemical element composition and concentration (in percent) to be determined. 

With the analysis of the carbon content, the carbon equivalent (CEV) can be calculated in order to make a statement about the basic weldability.

Small samples or samples in wire, powder or chip form can also be tested. These are remelted into a suitable test sample in a readily available vacuum furnace before spectrometry. When testing grey cast iron materials, the sample is first remelted to obtain a "white solidification".