ASTM C863-00(2022)

Standard Test Method for Evaluating Oxidation Resistance of Silicon Carbide Refractories at Elevated Temperatures

SIGNIFICANCE AND USE
3.1 The oxidation of silicon carbide refractories at elevated temperatures is an important consideration in the application of these refractories. The product of oxidation is amorphous silica or cristobalite, depending upon the temperature at which oxidation takes place. This oxide formation is associated with expansion and degradation of strength. The quantity of water vapor in the atmosphere greatly affects the rate of oxidation.  
3.2 The test, which creates and measures the expansion, is suitable for guidance in product development and relative comparison in application work where oxidation potential is of concern. The variability of the test is such that it is not recommended for use as a referee test.
SCOPE
1.1 This test method covers the evaluation of the oxidation resistance of silicon carbide refractories at elevated temperatures in an atmosphere of steam. The steam is used to accelerate the test. Oxidation resistance is the ability of the silicon carbide (SiC) in the refractory to resist conversion to silicon dioxide (SiO2) and its attendant crystalline growth.  
1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-Oct-2022
• ICS: 81.080 - Refractories
• Technical Committee: C08 - Refractories
• Drafting Committee: C08.04 - Chemical Behaviors

Relations

• Refers: ASTM C830-00(2011) - Standard Test Methods for Apparent Porosity, Liquid Absorption, Apparent Specific Gravity, and Bulk Density of Refractory Shapes by Vacuum Pressure
• Effective Date: 01-Jul-2011
• Refers: ASTM C914-09 - Standard Test Method for Bulk Density and Volume of Solid Refractories by Wax Immersion
• Effective Date: 01-Mar-2009
• Refers: ASTM C830-00(2006) - Standard Test Methods for Apparent Porosity, Liquid Absorption, Apparent Specific Gravity, and Bulk Density of Refractory Shapes by Vacuum Pressure
• Effective Date: 01-Jun-2006
• Refers: ASTM C20-00(2005) - Standard Test Methods for Apparent Porosity, Water Absorption, Apparent Specific Gravity, and Bulk Density of Burned Refractory Brick and Shapes by Boiling Water
• Effective Date: 01-Dec-2005
• Refers: ASTM C914-95(2004) - Standard Test Method for Bulk Density and Volume of Solid Refractories by Wax Immersion
• Effective Date: 01-Sep-2004
• Refers: ASTM C20-00 - Standard Test Methods for Apparent Porosity, Water Absorption, Apparent Specific Gravity, and Bulk Density of Burned Refractory Brick and Shapes by Boiling Water
• Effective Date: 10-Apr-2000
• Refers: ASTM C830-00 - Standard Test Methods for Apparent Porosity, Liquid Absorption, Apparent Specific Gravity, and Bulk Density of Refractory Shapes by Vacuum Pressure
• Effective Date: 10-Apr-2000
• Refers: ASTM C914-95(1999) - Standard Test Method for Bulk Density and Volume of Solid Refractories by Wax Immersion
• Effective Date: 01-Jan-1999

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C863 − 00 (Reapproved 2022)
Standard Test Method for
Evaluating Oxidation Resistance of Silicon Carbide
Refractories at Elevated Temperatures
This standard is issued under the fixed designation C863; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope these refractories.The product of oxidation is amorphous silica
or cristobalite, depending upon the temperature at which
1.1 This test method covers the evaluation of the oxidation
oxidation takes place. This oxide formation is associated with
resistance of silicon carbide refractories at elevated tempera-
expansion and degradation of strength. The quantity of water
tures in an atmosphere of steam. The steam is used to
vapor in the atmosphere greatly affects the rate of oxidation.
accelerate the test. Oxidation resistance is the ability of the
silicon carbide (SiC) in the refractory to resist conversion to 3.2 The test, which creates and measures the expansion, is
silicon dioxide (SiO ) and its attendant crystalline growth. suitable for guidance in product development and relative
comparison in application work where oxidation potential is of
1.2 This standard does not purport to address all of the
concern. The variability of the test is such that it is not
safety concerns, if any, associated with its use. It is the
recommended for use as a referee test.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
4. Apparatus
mine the applicability of regulatory limitations prior to use.
4.1 Heated Chamber—The chamber shall be muffled (Note
1.3 This international standard was developed in accor-
1) to confine the atmosphere. The size of the chamber and the
dance with internationally recognized principles on standard-
heat source are optional. The temperature capability within the
ization established in the Decision on Principles for the
chamber shall be at least 1200 °C (2190 °F) with an allowable
Development of International Standards, Guides and Recom-
deviation of 615 °C (27 °F) measured across the hearth.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee. NOTE 1—Silicon carbide refractory material is recommended for use as
the muffle but other suitable refractory materials may be used.
2. Referenced Documents
4.2 Instrument—Control and record the temperature of the
2.1 ASTM Standards: chamber by a suitable instrument capable of maintaining the
C20 Test Methods for Apparent Porosity, Water Absorption, requirements in 4.1. Recommended thermocouple location is
Apparent Specific Gravity, and Bulk Density of Burned within 1 in. (25 mm) of the top of the specimens and over the
Refractory Brick and Shapes by Boiling Water center of the same assemblage.
C830 Test Methods for Apparent Porosity, Liquid
5. Test Specimen
Absorption, Apparent Specific Gravity, and Bulk Density
5.1 Specimen Size—Obtain a quarter-brick size from a
of Refractory Shapes by Vacuum Pressure
229-mm (9-in.) straight by cutting the brick along planes
C914 Test Method for Bulk Density and Volume of Solid
parallel to both the 229-mm by 64-mm (9-in. by 2 ⁄2-in.) and
Refractories by Wax Immersion
1 1
the 114-mm by 64-mm (4 ⁄2-in. by 2 ⁄2-in.) faces. Alternative
3. Significance and Use
specimens may be tile, 165 mm by 114 mm by 22 mm
1 1 7
(6 ⁄2 in. by 4 ⁄2 in. by ⁄8 in.), or other convenient shapes.
3.1 The oxidation of silicon carbide refractories at elevated
temperaturesisanimportantconsiderationintheapplicationof
5.2 Three specimens are required for each set of conditions.
6. Conditions
This test method is under the jurisdiction of ASTM Committee C08 on
Refractories and is the direct responsibility of Subcommittee C08.04 on Chemical 6.1 Atmosphere—Steam is passed into the chamber (4.1)at
3 3
Behaviors.
the rate of 32 kg/m (2 lb/ft ) of chamber volume per hour.
Current edition approved Nov. 1, 2022. Published November 2022. Originally
Provisionsshouldbemadetouniformlydistributesteamwithin
approved in 1977. Last previous edition approved in 2016 as C863 – 00 (2016).
the chamber.
DOI: 10.1520/C0863-00R22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.2 The standard test temperatures are as follows wi
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