Lubricating oils are formulated with additives which act as detergents, coolants, anti-oxidants and anti-wear agents in engines. These additives typically contain calcium, copper, magnesium, phosphorus, sulfur and zinc compounds. To ensure the functionality of the lubricant, these compounds must be controlled. The respective elements can be measured and used to monitor the final compound concentrations in the oil.
In addition contaminants, such as chlorine, can influence the lubricant performance. A control of these elements is important to ensure a high product quality. The ASTM standard test method D 6443 describes how the added elements and chlorine are determined in lubrication products. This ASTM method is based on wavelength dispersive X-ray fluorescence (WDXRF) spectrometry.