ISO 21068-1:2008
Chemical analysis of silicon-carbide-containing raw materials and refractory products - Part 1: General information and sample preparation

Standard No.

ISO 21068-1:2008

Release Date

2008

Published By

International Organization for Standardization (ISO)

Latest

ISO 21068-1:2008

Scope

This part of ISO 21068 gives definitions and specifies techniques for the preparation of samples for the chemical analysis of silicon-carbidercontaining raw materials and refractory products including: a) graphite bdck containing silicon carbide; b) silicon carbide brick (includes the bricks containing silicon nitride); c) refractories containing carbon and/or silicon carbide mixed with clay; d) refractades containing carbon and/or silicon carbide mixed with silica (and fused silica); e) refractories containing carbon and/or silicon carbide mixed with high alumina material; f) refractories containing carbon and/or silicon carbide mixed with magnesia (and dolomite); g) refractories containing carbon and/or silicon carbide mixed with chrome mineral or magnesia chrome materials; h) refractories containing carbon and/or silicon carbide except those described in a) to g) above. The items of chemical analysis described in ISO 21068, Parts 1 to 3 are as follows: 1) loss on drying (LOD); 2) loss on ignition (LOI); 3) totalcarbon, Ctotal; 4) free carbon, Ceee; 5) silicon carbide, SiC; 6) free silicon (Si<(down）free>); 7) free aluminium (Al<(down）free>); 8) free magnesium (Mg<(down）free>); 9) freeiron (Fe<(down）free>); 10) silicon(IV) oxide (SiO2);11) aluminium oxide (AI203); 12) iron(Ill) oxide (total iron oxide calculated as Fe203); 13) titanium(IV) oxide (TiO2); 14) calcium oxide (CaO); 15) magnesium oxide (MgO); 16) sodium oxide (Na20); 17) potassium oxide (K20); 18) chromium(Ig) oxide (0r203); 19) zirconium oxide (ZrO2); 20) boron oxide (total boron calculated as B203); 21) nitrogen; 22) oxygen; 23) nitrides (undifferentiated: Si3N4, AIN, BN, sialon, oxy-nitrides, etc.).

ISO 21068-1:2008 Referenced Document

• EN 12698-2 Chemical analysis of nitride bonded silicon carbide refractories - Part 2: XRD methods
• ISO 12677:2003 Chemical analysis of refractory products by XRF - Fused cast bead method
• ISO 21068-2:2008 Chemical analysis of silicon-carbide-containing raw materials and refractory products - Part 2: Determination of loss on ignition, total carbon, free carbon and silicon carbide, total and free silica and total and free silicon
• ISO 31-0 Quantities and units - Part 0: General principles; Amendment 2
• ISO 5022 Shaped refractory products; Sampling and acceptance testing
• ISO 8656-1 Refractory products; sampling of raw materials and unshaped products; part 1: sampling scheme

ISO 21068-1:2008 history

• 2008 ISO 21068-1:2008 Chemical analysis of silicon-carbide-containing raw materials and refractory products - Part 1: General information and sample preparation