ASTM C863-00(2016)

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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-May-2016
• ICS: 81.080 - Refractories
• Technical Committee: C08 - Refractories
• Drafting Committee: C08.04 - Chemical Behaviors

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: C863 − 00 (Reapproved 2016)
Standard Test Method for
Evaluating Oxidation Resistance of Silicon Carbide
1
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 3.2 The test, which creates and measures the expansion, is
suitable for guidance in product development and relative
1.1 This test method covers the evaluation of the oxidation
comparison in application work where oxidation potential is of
resistance of silicon carbide refractories at elevated tempera-
concern. The variability of the test is such that it is not
tures in an atmosphere of steam. The steam is used to
recommended for use as a referee test.
accelerate the test. Oxidation resistance is the ability of the
silicon carbide (SiC) in the refractory to resist conversion to
4. Apparatus
silicon dioxide (SiO ) and its attendant crystalline growth.
2
4.1 Heated Chamber—The chamber shall be muffled (Note
1.2 This standard does not purport to address all of the
1) to confine the atmosphere. The size of the chamber and the
safety concerns, if any, associated with its use. It is the
heat source are optional. The temperature capability within the
responsibility of the user of this standard to establish appro-
chamber shall be at least 1200°C (2190°F) with an allowable
priate safety and health practices and determine the applica-
deviation of 615°C (27°F) measured across the hearth.
bility of regulatory limitations prior to use.
NOTE 1—Silicon carbide refractory material is recommended for use as
the muffle but other suitable refractory materials may be used.
2. Referenced Documents
2
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
Absorption, Apparent Specific Gravity, and Bulk Density
5. Test Specimen
of Refractory Shapes by Vacuum Pressure
5.1 Specimen Size—Obtain a quarter-brick size from a
C914 Test Method for Bulk Density and Volume of Solid
229-mm (9-in.) straight by cutting the brick along planes
Refractories by Wax Immersion
1
paralleltoboththe229by64-mm(9by2 ⁄2-in.)andthe114by
1 1
3. Significance and Use
64-mm (4 ⁄2 by 2 ⁄2-in.) faces. Alternative specimens may be
1 1 7
tile, 165 by 114 by 22 mm (6 ⁄2 by 4 ⁄2 by ⁄8 in.), or other
3.1 The oxidation of silicon carbide refractories at elevated
convenient shapes.
temperaturesisanimportantconsiderationintheapplicationof
these refractories.The product of oxidation is amorphous silica 5.2 Three specimens are required for each set of conditions.
or cristobalite, depending upon the temperature at which
6. Conditions
oxidation takes place. This oxide formation is associated with
expansion and degradation of strength. The quantity of water
6.1 Atmosphere—Steam is passed into the chamber (4.1)at
3 3
vapor in the atmosphere greatly affects the rate of oxidation.
the rate of 32 kg/m (2 lb/ft ) of chamber volume per hour.
Provisionsshouldbemadetouniformlydistributesteamwithin
the chamber.
1
This test method is under the jurisdiction of ASTM Committee C08 on
6.2 The standard test temperatures are as follows with new
Refractories and is the direct responsibility of Subcommittee C08.04 on Chemical
Behaviors.
samples used at each temperature. Each temperature consti-
Current edition approved June 1, 2016. Published June 2016. Originally
tutes a test.
approved in 1977. Last previous edition approved in 2010 as C863 – 00 (2010).
800°C (1470°F)
DOI: 10.1520/C0863-00R16.
2 900°C (1650°F)
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
1000°C (1830°F)
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
1100°C (2010°F)
Standards volume information, refer to the standard’s Document Summary page on
1200°C (2190°F)
the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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C863 − 00 (Reapproved 2016)
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C863 − 00 (2016)
The test temperature is selected on the basis of the specific 8. Report
needs that relate to the environment in which t
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C863 − 00 (Reapproved 2010) C863 − 00 (Reapproved 2016)
Standard Test Method for
Evaluating Oxidation Resistance of Silicon Carbide
1
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
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 (SiO ) and its attendant crystalline growth.
2
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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
C20 Test Methods for Apparent Porosity, Water Absorption, Apparent Specific Gravity, and Bulk Density of Burned Refractory
Brick and Shapes by Boiling Water
C830 Test Methods for Apparent Porosity, Liquid Absorption, Apparent Specific Gravity, and Bulk Density of Refractory Shapes
by Vacuum Pressure
C914 Test Method for Bulk Density and Volume of Solid Refractories by Wax Immersion
3. 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.
4. Apparatus
4.1 Heated Chamber—The chamber shall be muffled (Note 1) to confine the atmosphere. The size of the chamber and the heat
source are optional. The temperature capability within the chamber shall be at least 1200°C (2190°F) with an allowable deviation
of 615°C (27°F) measured across the hearth.
NOTE 1—Silicon carbide refractory material is recommended for use as the muffle but other suitable refractory materials may be used.
4.2 Instrument—Control and record the temperature of the chamber by a suitable instrument capable of maintaining the
requirements in 4.1. Recommended thermocouple location is within 1 in. (25 mm) of the top of the specimens and over the center
of the same assemblage.
5. Test Specimen
5.1 Specimen Size—Obtain a quarter-brick size from a 229-mm (9-in.) straight by cutting the brick along planes parallel to both
1 1 1
the 229 by 64-mm (9 by 2 ⁄2-in.) and the 114 by 64-mm (4 ⁄2 by 2 ⁄2-in.) faces. Alternative specimens may be tile, 165 by 114 by
1 1 7
22 mm (6 ⁄2 by 4 ⁄2 by ⁄8 in.), or other convenient shapes.
1
This test method is under the jurisdiction of ASTM Committee C08 on Refractories and is the direct responsibility of Subcommittee C08.04 on Chemical Behaviors.
Current edition approved Nov. 1, 2010June 1, 2016. Published November 2010 June 2016. Originally approved in 1977. Last previous edition approved in 20052010 as
C863 – 00 (2005).(2010). DOI: 10.1520/C0863-00R10.10.1520/C0863-00R16.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
C863 − 00 (2016)
5.2 Three specimens are required for each set of conditions.
6. Conditions
3 3
6.1 Atmosphere—Steam is passed into the chamber (4.1) at the rate of 32 kg/m (2 lb/ft ) of chamber volume per hour.
Provisions should be made to uniformly distribute steam within the chamber.
6.2 The standard test tempe
...