ASTM E526-08

Standard Test Method for Measuring Fast-Neutron Reaction Rates by Radioactivation of Titanium

SIGNIFICANCE AND USE
Refer to Guide E 844 for the selection, irradiation, and quality control of neutron dosimeters.
Refer to Test Method E 261 for a general discussion of the determination of fast-neutron fluence rate with threshold detectors.
Titanium has good physical strength, is easily fabricated, has excellent corrosion resistance, has a melting temperature of 1675°C, and can be obtained with satisfactory purity.
46Sc has a half-life of 83.79 days. The 46Sc decay emits a 0.8893 MeV gamma 99.984 % of the time and a second gamma with an energy of 1.1205 MeV 99.987 % of the time.
The isotopic content of natural titanium recommended for 46Ti is 8.25 %.  
The radioactive products of the neutron reactions 47Ti(n,p)47Sc (τ1/2 = 3.3492 d) and 48Ti(n,p)48Sc (τ1/2  = 43.67 h), might interfere with the analysis of 46Sc.
Contaminant activities (for example, 65Zn and 182Ta) might interfere with the analysis of 46Sc. See Sections 7.1.2 and 7.1.3 for more details on the 182Ta and 65Zn interference.
46Ti and 46Sc have cross sections for thermal neutrons of 0.59 and 8 barns, respectively ; therefore, when an irradiation exceeds a thermal-neutron fluence greater than about 2 × 1021  cm–2, provisions should be made to either use a thermal-neutron shield to prevent burn-up of 46Sc or measure the thermal-neutron fluence rate and calculate the burn-up.
Fig. 1 shows a plot of cross section versus neutron energy for the fast-neutron reactions of titanium which produce 46Sc [that is, NatTi(n,X)46Sc]. Included in the plot is the 46Ti(n,p) reaction and the 47Ti(n,np) contribution to the 46Sc production, normalized (at 14.7 MeV) per 46Ti atom. This figure is for illustrative purposes only to indicate the range of response of the 46Ti(n,p) reaction. Refer to Guide E 1018 for descriptions of recommended tabulated dosimetry cross sections.
SCOPE
1.1 This test method covers procedures for measuring reaction rates by the activation reactions 46Ti(n,p) 46Sc + 47Ti(n, np)46Sc.
Note 1—Since the cross section for the (n,np) reaction is relatively small for energies less than 12 MeV and is not easily distinguished from that of the (n,p) reaction, this test method will refer to the (n,p) reaction only.
1.2 The reaction is useful for measuring neutrons with energies above approximately 4.4 MeV and for irradiation times up to about 250 days (for longer irradiations, see Practice E 261).
1.3 With suitable techniques, fission-neutron fluence rates above 109  cm–2·s–1  can be determined. However, in the presence of a high thermal-neutron fluence rate,  46Sc depletion should be investigated.
1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E 261.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 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: 30-Jun-2008
• ICS: 17.240 - Radiation measurements
• ICS: 27.120.30 - Fissile materials and nuclear fuel technology
• Technical Committee: E10 - Nuclear Technology and Applications
• Drafting Committee: E10.05 - Nuclear Radiation Metrology

Relations

• Replaces: ASTM E526-97(2002) - Standard Test Method for Measuring Fast-Neutron Reaction Rates by Radioactivation of Titanium
• Effective Date: 01-Jul-2008
• Replaced By: ASTM E526-08(2013) - Standard Test Method for Measuring Fast-Neutron Reaction Rates by Radioactivation of Titanium
• Effective Date: 01-Jan-2013
• Referred By: ASTM E944-19 - Standard Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance
• Effective Date: 01-Jul-2008
• Referred By: ASTM E721-22 - Standard Guide for Determining Neutron Energy Spectra from Neutron Sensors for Radiation-Hardness Testing of Electronics
• Effective Date: 01-Jul-2008
• Referred By: ASTM E2005-21 - Standard Guide for Benchmark Testing of Reactor Dosimetry in Standard and Reference Neutron Fields
• Effective Date: 01-Jul-2008
• Referred By: ASTM E1854-19 - Standard Practice for Ensuring Test Consistency in Neutron-Induced Displacement Damage of Electronic Parts
• Effective Date: 01-Jul-2008
• Referred By: ASTM E261-16(2021) - Standard Practice for Determining Neutron Fluence, Fluence Rate, and Spectra by Radioactivation Techniques
• Effective Date: 01-Jul-2008
• Referred By: ASTM E1005-21 - Standard Test Method for Application and Analysis of Radiometric Monitors for Reactor Vessel Surveillance
• Effective Date: 01-Jul-2008

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: E526 − 08
StandardTest Method for
Measuring Fast-Neutron Reaction Rates by Radioactivation
1
of Titanium
This standard is issued under the fixed designation E526; 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 E181Test Methods for Detector Calibration andAnalysis of
Radionuclides
1.1 This test method covers procedures for measuring reac-
46 46 47 E261Practice for Determining Neutron Fluence, Fluence
tion rates by the activation reactions Ti(n,p) Sc + Ti(n,
46
Rate, and Spectra by Radioactivation Techniques
np) Sc.
E262Test Method for Determining Thermal Neutron Reac-
NOTE 1—Since the cross section for the (n,np) reaction is relatively
tion Rates and Thermal Neutron Fluence Rates by Radio-
small for energies less than 12 MeV and is not easily distinguished from
activation Techniques
that of the (n,p) reaction, this test method will refer to the (n,p) reaction
E844Guide for Sensor Set Design and Irradiation for
only.
Reactor Surveillance, E 706 (IIC)
1.2 The reaction is useful for measuring neutrons with
E944Guide for Application of Neutron Spectrum Adjust-
energies above approximately 4.4 MeV and for irradiation
ment Methods in Reactor Surveillance, E 706 (IIA)
timesuptoabout250days(forlongerirradiations,seePractice
E1005Test Method for Application and Analysis of Radio-
E261).
metric Monitors for Reactor Vessel Surveillance, E 706
1.3 With suitable techniques, fission-neutron fluence rates
(IIIA)
9 –2 –1
above 10 cm ·s can be determined. However, in the pres-
E1018Guide for Application of ASTM Evaluated Cross
46
ence of a high thermal-neutron fluence rate, Sc depletion
Section Data File, Matrix E706 (IIB)
should be investigated.
1.4 Detailed procedures for other fast-neutron detectors are
3. Terminology
referenced in Practice E261.
3.1 Definitions:
1.5 The values stated in SI units are to be regarded as
3.1.1 Refer to Terminology E170.
standard. No other units of measurement are included in this
standard.
4. Summary of Test Method
1.6 This standard does not purport to address all of the
4.1 High-purity titanium is irradiated in a fast-neutron field,
safety concerns, if any, associated with its use. It is the
46 46 46
thereby producing radioactive Sc from the Ti(n,p) Sc
responsibility of the user of this standard to establish appro-
activation reaction.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
4.2 The gamma rays emitted by the radioactive decay of
46
Sc are counted in accordance with Methods E181 and the
2. Referenced Documents
reaction rate, as defined by Test Method E261, is calculated
2
2.1 ASTM Standards:
from the decay rate and the irradiation conditions.
E170Terminology Relating to Radiation Measurements and
4.3 The neutron fluence rate above about 4.4 MeV can then
Dosimetry
be calculated from the spectral-weighted neutron activation
cross section as defined by Test Method E261.
1
ThistestmethodisunderthejurisdictionofASTMCommitteeE10onNuclear
Technology and Applicationsand is the direct responsibility of Subcommittee
5. Significance and Use
E10.05 on Nuclear Radiation Metrology.
Current edition approved July 1, 2008. Published September 2008. Originally
5.1 Refer to Guide E844 for the selection, irradiation, and
approved in 1976. Last previous edition approved in 2002 as E526–97 (2002).
quality control of neutron dosimeters.
DOI: 10.1520/E0526-08.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
5.2 Refer to Test Method E261 for a general discussion of
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
the determination of fast-neutron fluence rate with threshold
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. detectors.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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E526 − 08
46 6 47 46
5.3 Titanium has good physical strength, is easily Ti(n,p)reaction andthe Ti(n,np)contributiontothe Sc
7 8 46
fabricated, has excellent corrosion resistance, has a melting production, normalized (at 14.7 MeV) per Ti atom. This
temperature of 1675°C, and can be obtained with satisfactory figure is for illustrative purposes only to indicate the range of
46
purity. response of the Ti(n,p) reaction. Refer to Guide E1018 for
46 3 46 4 descriptions of recommended tabulated dosimetry cross sec-
5.4 Sc has a half-life of 83.79 days. The Sc decay
tions.
emitsa0.8893MeVgamma99.984%ofthetimeandasecond
gamma with an energy
...

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:E526–97 (Reapproved 2002) Designation: E 526 – 08
Standard Test Method for
Measuring Fast-Neutron Reaction Rates by Radioactivation
1
of Titanium
This standard is issued under the fixed designation E 526; 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
46 46 47 46
1.1 Thistestmethodcoversproceduresformeasuringreactionratesbytheactivationreactions Ti(n,p) Sc+ Ti(n,np) Sc.
NOTE 1—Since the cross section for the (n,np) reaction is relatively small for energies less than 12 MeV and is not easily distinguished from that of
the (n,p) reaction, this test method will refer to the (n,p) reaction only.
1.2 The reaction is useful for measuring neutrons with energies above approximately 4.4 MeV and for irradiation times up to
about 250 days (for longer irradiations, see Practice E 261).
9 –2 –1
1.3 With suitable techniques, fission-neutron fluence rates above 10 cm ·s can be determined. However, in the presence of
46
a high thermal-neutron fluence rate, Sc depletion should be investigated.
1.4 Detailed procedures for other fast-neutron detectors are referenced in Practice E 261.
1.5
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 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:
E 170 Terminology Relating to Radiation Measurements and Dosimetry
E 181 Test Methods for Detector Calibration and Analysis of Radionuclides
E 261 Practice for Determining Neutron Fluence, Fluence Rate, Fluence, and Spectra by Radioactivation Techniques
E 262 Test Method for Determining Thermal Neutron Reaction and Fluence Rates by Radioactivation Techniques
2
E 844 Guide for Sensor Set Design and Irradiation for Reactor Surveillance, E706 (IIC) E 706(IIC)
E 944 Guide for Application of Neutron Spectrum Adjustment Methods in Reactor Surveillance, E 706 (IIA)
2
E 1005 Test Method for Application and Analysis of Radiometric Monitors for Reactor Vessel Surveillance, E706 (IIIA) E
706(IIIA)
E 1018 Guide for Application of ASTM Evaluated Cross Section Data Files,File, Matrix E 706 (IIB)
3. Terminology
3.1 Definitions:
3.1.1 Refer to Terminology E 170.
4. Summary of Test Method
46 46 46
4.1 High-purity titanium is irradiated in a fast-neutron field, thereby producing radioactive Sc from the Ti(n,p) Sc
activation reaction.
46
4.2 The gamma rays emitted by the radioactive decay of Sc are counted in accordance with Methods E 181 and the reaction
rate, as defined by Test Method E 261, is calculated from the decay rate and the irradiation conditions.
4.3 The neutron fluence rate above about 4.4 MeV can then be calculated from the spectral-weighted neutron activation cross
section as defined by Test Method E 261.
1
This test method is under the jurisdiction of ASTM Committee E10 on Nuclear Technology and Applications and is the direct responsibility of Subcommittee E10.05
on Nuclear Radiation Metrology.
Current edition approved June 10, 1997. Published May 1998. Originally published as E526–76. Last previous edition E526–92.
Current edition approved July 1, 2008. Published September 2008. Originally approved in 1976. Last previous edition approved in 2002 as E 526 – 97 (2002).
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
, Vol 12.02.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

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E526–08
5. Significance and Use
5.1 Refer to Guide E 844 for the selection, irradiation, and quality control of neutron dosimeters.
5.2 Refer to Test Method E 261 for a general discussion of the determination of fast-neutron fluence rate with threshold
detectors.
5.3 Titanium has good physical strength, is easily fabricated, has excellent corrosion resistance, has a melting temperature of
1675°C, and can be obtai
...