ASTM E942-96(2003)

Standard Guide for Simulation of Helium Effects in Irradiated Metals

ABSTRACT
This guide presents the simulation procedure which would provide advice for conducting experiments to investigate the effects of helium on the properties of irradiated metals where the technique for introducing the helium differs in someway from the actual mechanism of introduction of helium in service. Simulation techniques considered for introducing helium shall include charged particle implantation, exposure to α-emitting radioisotopes, and tritium decay techniques. Procedures for the analysis of helium content and helium distribution within the specimen are also recommended. The two other methods for introducing helium into irradiated materials namely, the enhancement of helium production in nickel-bearing alloys by spectral tailoring in mixed-spectrum fission reactors, and the isotopic tailoring in both fast and mixed-spectrum fission reactors, are not covered in this guide. Dual ion beam techniques for simultaneously implanting helium and generating displacement damage are also not included here.
SIGNIFICANCE AND USE
Helium is introduced into metals as a consequence of nuclear reactions, such as (n, α), or by the injection of helium into metals from the plasma in fusion reactors. The characterization of the effect of helium on the properties of metals using direct irradiation methods may be impractical because of the time required to perform the irradiation or the lack of a radiation facility, as in the case of the fusion reactor. Simulation techniques can accelerate the research by identifying and isolating major effects caused by the presence of helium. The word simulation is used here in a broad sense to imply an approximation of the relevant irradiation environment. There are many complex interactions between the helium produced during irradiation and other irradiation effects, so care must be exercised to ensure that the effects being studied are a suitable approximation of the real effect. By way of illustration, details of helium introduction, especially the implantation temperature, may determine the subsequent distribution of the helium (that is, dispersed atomistically, in small clusters in bubbles, etc.)
SCOPE
1.1 This guide provides advice for conducting experiments to investigate the effects of helium on the properties of metals where the technique for introducing the helium differs in some way from the actual mechanism of introduction of helium in service. Simulation techniques considered for introducing helium shall include charged particle implantation, exposure to -emitting radioisotopes, and tritium decay techniques. Procedures for the analysis of helium content and helium distribution within the specimen are also recommended.
1.2 Two other methods for introducing helium into irradiated materials are not covered in this guide. They are the enhancement of helium production in nickel-bearing alloys by spectral tailoring in mixed-spectrum fission reactors, and isotopic tailoring in both fast and mixed-spectrum fission reactors. These techniques are described in Refs (1-5). Dual ion beam techniques (6) for simultaneously implanting helium and generating displacement damage are also not included here. This latter method is discussed in Practice E 521.
1.3 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: 09-Jan-1996
• Technical Committee: E10 - Nuclear Technology and Applications

Relations

• Replaces: ASTM E942-96 - Standard Guide for Simulation of Helium Effects in Irradiated Metals
• Effective Date: 10-Jan-1996
• Replaced By: ASTM E942-96(2011) - Standard Guide for Simulation of Helium Effects in Irradiated Metals
• Effective Date: 15-Jun-2011
• Referred By: ASTM E521-23 - Standard Practice for Investigating the Effects of Neutron Radiation Damage Using Charged-Particle Irradiation
• Effective Date: 10-Jan-1996

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:E942–96 (Reapproved 2003)
Standard Guide for
1
Simulation of Helium Effects in Irradiated Metals
This standard is issued under the fixed designation E942; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E521 Practice for Neutron Radiation Damage Simulation
by Charged-Particle Irradiation
1.1 This guide provides advice for conducting experiments
E706 Master Matrix for Light-Water Reactor Pressure Ves-
to investigate the effects of helium on the properties of metals
sel Surveillance Standards, E 706(0)
where the technique for introducing the helium differs in some
E910 Test Method for Application and Analysis of Helium
way from the actual mechanism of introduction of helium in
Accumulation Fluence Monitors for Reactor Vessel Sur-
service. Simulation techniques considered for introducing he-
veillance, E706 (IIIC)
lium shall include charged particle implantation, exposure to
a-emitting radioisotopes, and tritium decay techniques. Proce-
3. Terminology
duresfortheanalysisofheliumcontentandheliumdistribution
3.1 DescriptionsofrelevanttermsarefoundinTerminology
within the specimen are also recommended.
C859 and Terminology E170.
1.2 Two other methods for introducing helium into irradi-
ated materials are not covered in this guide. They are the
4. Significance and Use
enhancement of helium production in nickel-bearing alloys by
4.1 Helium is introduced into metals as a consequence of
spectral tailoring in mixed-spectrum fission reactors, and
nuclear reactions, such as (n, a), or by the injection of helium
isotopic tailoring in both fast and mixed-spectrum fission
2 into metals from the plasma in fusion reactors. The character-
reactors. These techniques are described in Refs (1-5). Dual
izationoftheeffectofheliumonthepropertiesofmetalsusing
ion beam techniques (6) for simultaneously implanting helium
direct irradiation methods may be impractical because of the
and generating displacement damage are also not included
time required to perform the irradiation or the lack of a
here. This latter method is discussed in Practice E521.
radiation facility, as in the case of the fusion reactor. Simula-
1.3 This standard does not purport to address all of the
tion techniques can accelerate the research by identifying and
safety concerns, if any, associated with its use. It is the
isolating major effects caused by the presence of helium. The
responsibility of the user of this standard to establish appro-
word simulation is used here in a broad sense to imply an
priate safety and health practices and determine the applica-
approximation of the relevant irradiation environment. There
bility of regulatory limitations prior to use.
are many complex interactions between the helium produced
2. Referenced Documents during irradiation and other irradiation effects, so care must be
3 exercised to ensure that the effects being studied are a suitable
2.1 ASTM Standards:
approximation of the real effect. By way of illustration, details
C859 Terminology Relating to Nuclear Materials
of helium introduction, especially the implantation tempera-
E170 TerminologyRelatingtoRadiationMeasurementsand
ture, may determine the subsequent distribution of the helium
Dosimetry
(that is, dispersed atomistically, in small clusters in bubbles,
etc.)
1
This guide is under the jurisdiction of ASTM Committee E10 on Nuclear
5. Techniques for Introducing Helium
Technology and Applications and is the direct responsibility of Subcommittee
E10.08 on Procedures for Neutron Radiation Damage Simulation.
5.1 Implantation of Helium Using Charged Particle Accel-
Current edition approved July 10, 2003. Published July 2003. Originally
erators:
approved in 1983. Last previous edition approved in 1996 as E942–96. DOI:
5.1.1 Summary of Method—Charged particle accelerators
10.1520/E0942-96R03.
2
aredesignedtodeliverwelldefined,intensebeamsofmonoen-
The boldface numbers in parentheses refer to a list of references at the end of
this guide.
ergetic particles on a target. They thus provide a convenient,
3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
rapid, and relatively inexpensive means of introducing large
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
concentrations of helium into thin specimens. An energetic
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. alphaparticleimpingingonatargetlosesenergybyexcitingor
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