Значение и использование

Property data obtained with the recommended test methods identified herein may be used for research and development, design, manufacturing control, specifications, performance evaluation, and regulatory statutes pertaining to high temperature gas-cooled reactors.

The test methods are applicable primarily to specimens in the non-irradiated and non-oxidized state. Many are also applicable to specimens in the irradiated or oxidized state, or both, provided the specimens meet all requirements of the test method. The user is cautioned to consider the instructions given in the test methods.

Additional test methods are in preparation and will be incorporated. The user is cautioned to employ the latest revision.

Область применения

1.1 This practice covers the test methods for measuring the properties of graphite and boronated graphite materials. These properties may be used for the design and evaluation of high-temperature gas-cooled reactor components.

1.2 The test methods referenced herein are applicable to materials used for replaceable and permanent components as defined in Section 7 and Section 9, and includes fuel elements; removable reflector elements and blocks; permanent side reflector elements and blocks; core support pedestals and elements; control rod, reserve shutdown, and burnable poison compacts; and neutron shield material.

1.3 This practice includes test methods that have been selected from existing ASTM standards, ASTM standards that have been modified, and new ASTM standards that are specific to the testing of materials listed in 1.2. Comments on individual test methods for graphite and boronated graphite components are given in Sections 8 and 10, respectively. The test methods are summarized in Tables 1 and 2.

1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.

1.5 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.

TABLE 1 Summary of Test Methods for Graphite Components

Note—Designations under preparation will be added when approved.

Fuel, Removable Reflector,
and Core Support Elements;
Pebble Bed Reflector,
Key and Sleeves;
and Dowel PinsPermanent Side
Reflector Elements
and Dowel PinsCore Support Pedestals
and Dowels Fabrication As Manufactured Bulk DensityC838C838C838 Mechanical Properties Compressive StrengthC695C695C695 Tensile PropertiesC749^AC749^AC749^A Poisson’s RatioE132^BE132^BE132^B Flexural StrengthC651^AC651^AC651^A Fracture Toughness^BBB Modulus of ElasticityC747C747C747 Physical Properties Bulk Density–Machined SpecimensC559C559C559 Surface Area (BET)C1274C1274C1274 PermeabilityC577^A,BC577^A,BC577^A,B Apparent PorosityC1039C1039C1039 Spectroscopic Analysis^BBB Electrical ResistivityC611C611C611 Thermal Properties Linear Thermal ExpansionE228^A Thermal ConductivityE1461^AE1461^AE1461^A Chemical Properties Oxidative Mass LossC1179^BC1179^BC1179^B Sulfur ConcentrationC816C816C816 Ash ContentC561^AC561^AC561^A Equivalent Boron ContentC1233^AC1233^AC

^A Modification of this test method is required. See Section 8 for details.

^B New test methods are required. See Section 8 for details.

^C There is no identified need for determining this property.

TABLE 2 Summary of Test Methods for Boronated Graphite Components

Note—Designations under preparation will be added when approved.

CompactsNeutron
Shield
Material Control
RodBurnable
PoisonReserve
Shutdown Bulk DensityC838C838C838D4292 Linear Thermal Expansion^AE228^AE228^AB Particle Size^CCCD2862 Mechanical Strength: Compressive StrengthC695^AC695^AC695^AB Impact Performance^BBBC Chemical Properties: Sulfur Concentration^CCCC Hafnium Concentration^CCCC Relative Oxidation Rate^CCCC Boron Analysis: Total Boron^CCCC Boron as Oxide^CCCC B₄C Particle SizeD2862^DD2862^DD2862^DD2862^D

^A Modification of this test method is required. See Section 10 for details.

^B There is no identified need for determining this property.

^C New test methods are required. See Section 10 for details.

^D Additional test methods are required. See Section 10 for details.