Chemical analysis of raw materials and refractory products containing silicon-carbide, silicon-nitride, silicon-oxynitride and sialon — Part 1: General information, terminology and sample preparation

This document gives definitions and specifies techniques for the preparation of samples for the chemical analysis of silicon-carbide-containing raw materials and refractory products including:

a) SiC raw materials;

b) graphite brick containing silicon carbide;

c) silicon carbide brick (includes the bricks containing silicon nitride, silicon oxynitride, sialon);

d) refractories containing carbon and/or silicon carbide mixed with clay;

e) refractories containing carbon and/or silicon carbide mixed with silica (and fused silica);

f) refractories containing carbon and/or silicon carbide mixed with high alumina material;

g) refractories containing carbon and/or silicon carbide mixed with magnesia (and dolomite);

h) refractories containing carbon and/or silicon carbide mixed with chrome mineral or magnesia-chrome materials;

i) refractories containing carbon and/or silicon carbide except those described in a) to h) above.

The items of analysis described in ISO 21068-2, ISO 21068-3 and ISO 21068-4 are as follows:

— loss on drying (LOD);

— loss on ignition (LOI);

— total carbon, Ctotal;

— free carbon, Cfree;

— silicon carbide, SiC;

— free silicon (Sifree);

— free aluminium