Significance and Use
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.
Scope
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 Pins | Permanent Side Reflector Elements and Dowel Pins | Core Support Pedestals and Dowels | |
|---|---|---|---|
| Fabrication | |||
| As Manufactured Bulk Density | C838 | C838 | C838 |
| Mechanical Properties | |||
| Compressive Strength | C695 | C695 | C695 |
| Tensile Properties | C749A | C749A | C749A |
| Poisson’s Ratio | E132B | E132B | E132B |
| Flexural Strength | C651A | C651A | C651A |
| Fracture Toughness | B | B | B |
| Modulus of Elasticity | C747 | C747 | C747 |
| Physical Properties | |||
| Bulk Density–Machined Specimens | C559 | C559 | C559 |
| Surface Area (BET) | C1274 | C1274 | C1274 |
| Permeability | C577A,B | C577A,B | C577A,B |
| Apparent Porosity | C1039 | C1039 | C1039 |
| Spectroscopic Analysis | B | B | B |
| Electrical Resistivity | C611 | C611 | C611 |
| Thermal Properties | |||
| Linear Thermal Expansion | E228A | ||
| Thermal Conductivity | E1461A | E1461A | E1461A |
| Chemical Properties | |||
| Oxidative Mass Loss | C1179B | C1179B | C1179B |
| Sulfur Concentration | C816 | C816 | C816 |
| Ash Content | C561A | C561A | C561A |
| Equivalent Boron Content | C1233A | C1233A | C |
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.
| Compacts | Neutron Shield Material | |||
|---|---|---|---|---|
| Control Rod | Burnable Poison | Reserve Shutdown | ||
| Bulk Density | C838 | C838 | C838 | D4292 |
| Linear Thermal Expansion | A | E228A | E228A | B |
| Particle Size | C | C | C | D2862 |
| Mechanical Strength: | ||||
| Compressive Strength | C695A | C695A | C695A | B |
| Impact Performance | B | B | B | C |
| Chemical Properties: | ||||
| Sulfur Concentration | C | C | C | C |
| Hafnium Concentration | C | C | C | C |
| Relative Oxidation Rate | C | C | C | C |
| Boron Analysis: | ||||
| Total Boron | C | C | C | C |
| Boron as Oxide | C | C | C | C |
| B4C Particle Size | D2862D | D2862D | D2862D | D2862D |
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.
