Meaning
International standards specify a method for the chemical analysis of ceramic and refractory materials using x-ray fluorescence on fused cast beads. Application of iso 12677 ensures high precision when determining the composition of mineral additives used in heat resistant polymers.
Sample Preparation
Raw materials are ground to a fine powder and mixed with a lithium borate flux before being melted at high temperatures. This process destroys the mineralogical history of the sample and creates a homogeneous glass disc. By following iso 12677, particle size effects are eliminated that would otherwise skew the measurement of silica or alumina content.
Quality Control
Reference materials of known purity are used to calibrate the spectrometer against the target oxides. Precise measurement of the iron oxide or titania levels in a filler helps avoid discoloration in the final moulded part. Minor variations in the flux to sample ratio can be corrected by weighing the final bead and comparing it to the initial components.
Systematic Accuracy
Errors are minimized by accounting for the mass loss during the fusion process. This loss on ignition represents the removal of water and carbon dioxide from the mineral. Adherence to the weighing protocols in iso 12677 prevents the accumulation of bias in the final analytical report.
