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Sample Pretreatment For Optical Emission Spectrometry
Samples are taken from molten metal, thin sheet, semi-complete or complete products. When sampling molten metal with a ladle, small quantities of molten metal are poured into a casting mold. Unnecessary parts of the sample are removed using a grinder or a cutter. As particles from a grinder may contaminate the surface of the sample, a lathe or milling machine is used (not a grinder) to cut soft samples such as white metal. If trace elements are not being investigated, a grinder or belt sander can be used. However, to minimize contamination, the grinding wheel or belt should be changed for each sample. Samples excised from semi-complete or complete products must be at least 12 mm in diameter. Small rod-shaped samples can be analyzed using special equipment.