PMI is used to identify the composition of the parent and filler materials to ensure they meet the governing code requirements. Our X-ray fluorescence analyzers provide alloy chemistry and grade ID information in seconds using a hand-held scanner. When materials are exposed to short-wavelength X-rays or to gamma rays, ionization of their component atoms may take place. The removal of an electron in this way makes the electronic structure of the atom unstable and energy is released in the form of a photon. Thus, the material emits radiation, which has energy characteristic of the atoms present. The term fluorescence is applied to phenomena in which the absorption of radiation of a specific energy results in the re-emission of radiation of a different energy (generally lower). The fluorescent radiation can be analysed. Once sorted, the intensity of each characteristic radiation is directly related to the amount of each element in the material. This is the basis of X-ray fluorescence PMI.