In cast irons, the carbon, silicon and nodularizing magnesium contents determine the graphite structure, the matrix and therefore the mechanical properties. Chemical analysis is used to verify casting quality and, together with microstructure examination, in failure analysis. Analysis is performed with a spark optical emission spectrometer (spark OES): a spark on the specimen surface excites the elements so that each emits light at its own wavelength, and element contents are determined in percent from the light intensity.
The test is performed with a method accredited by TÜRKAK under TS EN ISO/IEC 17025 (ASTM E1999); results are issued as an accredited test report.
Elements Determined
- C, Si, Mn, P, Cr, Ni, Mg, Cu, Ti, V, Sn, Mo
Applied Standard
- ASTM E1999 – Analysis of cast iron by spark atomic emission spectrometry
Specimens and Reporting
A white-solidified (graphite-free) specimen gives the most accurate result; for specimens taken from castings, the surface is prepared accordingly. Several sparks are taken on each specimen and the mean is reported; on request, results are compared with the limits of the relevant material standard.