ISO 21068-4:2024

This document describes methods for the determination of mineralogical phases typically apparent in nitride and oxy-nitride bonded silicon carbide refractory products using a Bragg-Brentano diffractometer. It includes details of sample preparations and general principles for qualitative and quantitative analyses of mineralogical phase composition. Quantitative determination of α-Si3N4, β-Si3N4, Si2ON2, AlN, and β’- SiAlON are described. For quantitative determination of α-Si3N4, β-Si3N4, Si2ON2, AlN and β’-SiAlON refinement procedures based on the total nitrogen content of the sample are described. NOTE            ISO 21068-3 is used for the analysis of the total nitrogen content of the sample.