1、Designation: E1253 07E1253 13Standard Guide forReconstitution of Irradiated Charpy-Sized Specimens1This standard is issued under the fixed designation E1253; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers procedures for the reconstitution of ferritic pressure boundaryvessel steels used in nuclear power plantapplicati
3、ons, TypeACharpy (Test Methods E23) specimens and Charpy-sized specimens suitable for testing in three point bendingin accordance with Test Methods E1921 or E1820. Materials from irradiation programs (principally broken specimens) arereconstituted by welding end tabs of similar material onto remachi
4、ned specimen sections that were unaffected by the initial test.Guidelines are given for the selection of suitable specimen halves and end tab materials, for dimensional control, and for avoidanceof overheating the notch area. A comprehensive overview of the reconstitution methodologies can be found
5、in Ref (1).21.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard t
6、o establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3E23 Test Methods for Notched Bar Impact Testing of Metallic MaterialsE185 Practice for Design of Surveillance Programs for Light-Water
7、Moderated Nuclear Power Reactor VesselsE220 Test Method for Calibration of Thermocouples By Comparison TechniquesE1820 Test Method for Measurement of Fracture ToughnessE1921 Test Method for Determination of Reference Temperature, To, for Ferritic Steels in the Transition RangeE2215 Practice for Eval
8、uation of Surveillance Capsules from Light-Water Moderated Nuclear Power Reactor Vessels3. Significance and Use3.1 Practice E185 defines the minimum requirements for light-water reactor surveillance program Charpy V-notch specimensand Practice E2215 describes the evaluation of test specimens from su
9、rveillance capsules. It may be desirable to extend the originalsurveillance program beyond available specimens for plant aging management issues, such as plant license renewal, to better defineexisting data, or to determine fracture toughness of a material when no standard fracture toughness test sp
10、ecimens are available.The ability to reconstitute the broken halves of existing specimens can provide such data.3.2 Charpy-sized specimens are typically machined from virgin material, that is, material not previously mechanically tested.There are occasions that exist when either (1) no full size spe
11、cimen blanks are available or (2) the material available with thedesired history (such as having been subjected to irradiation) is not sufficient for the machining of full-size specimens, or both.3.3 An approachsolution to this problem, which is addressed in this guide, is to fabricate new specimens
12、 using the broken halvesof previously irradiated and tested specimens or other material irradiated for this purpose. In this guide, the central segment of eachnew specimen utilizes a broken half of a previously tested specimen and end tabs that are welded to the central segment, or thecentral sectio
13、n may simply be a piece of virgin material shorter than a Charpy-sized specimen. While specifically addressingreconstitution of irradiated pressure vessel steel,steels, this guide can also provide guidance for reconstitution of Charpy-sizedspecimens for other situations involving material availabili
14、ty.1 This guide is under the jurisdiction of ASTM Committee E10 on Nuclear Technology and Applicationsand is the direct responsibility of Subcommittee E10.02 onBehavior and Use of Nuclear Structural Materials.Current edition approved Feb. 1, 2007Jan. 1, 2013. Published March 2007January 2013. Origin
15、ally approved in 1993. Last previous edition approved in 19992007 asE1253-99.-07. DOI: 10.1520/E1253-07.10.1520/E1253-13.2 The boldface numbers in parentheses refer to the list of references at the end of this standard.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactAS
16、TM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.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 mad
17、e to the previous version. Becauseit 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 versionof the standard as published by ASTM is to be considered the official document.Copy
18、right ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. Reconstitution Technique4.1 Welding Process:4.1.1 Any welding process may be chosen, provided that the heat input and dimensional constraints, as givenprescribed in thisguide, can be achi
19、eved. Work to date has indicated successful results with stud welding (2), electron beam welding (3,4), andprojection welding (5), and laser welding (6).4.2 Specimen Preparation:4.2.1 The specimen insert used for reconstitution and its orientation shall be identified such that it can be traced to th
20、e originalspecimen. Fig. 1 illustrates the components of the reconstituted specimen and defines several terms used in the followingdiscussion. The central test section of the insert lies between the heat-affected zones (HAZ) created by the reconstitution welds.Within this central test section, the t
21、emperature during reconstitution welding shall not exceed the irradiation temperature in a10-mm (0.39-in.) region centered about the notch.4.2.2 Each end face of the specimen insert and the selected extension tabs shall be prepared as required by the particular weldingmethod selected.4.2.3 If compar
22、able data between the original and reconstituted testsspecimens are required, then the orientation of thereconstituted specimen and of the original specimen must be identical.4.2.4 The strength and the material type of the end tabs shouldshall be similar to the specimen insert. This can be important
23、,especially in the case of irradiated (highly hardened) materials. Strength or hardness and material type for the end tabs and centralinsert shall be documented. Differences within a defined range were shown not to influence the test results (67). The use ofoversized tabs and subsequent machining is
24、 permitted.4.2.5 It is important to ensure that the plastic deformation beneath the notch, produced when the reconstituted specimen istested, will occur entirely within previously undeformed material in the central test section. The following guidelines are providedto meet this objective:4.2.5.1 To
25、ensure that the specimen insert volume, subjected to plastic deformation during the subsequent testing, is free of priorplastic deformation, sufficient material shall be removed from the fractured end of the broken specimen half. Some plasticdeformation on either end of the original insert can be ac
26、cepted if it is outside the central 10 mm (0.40 in.) portion.10-mm (0.39-in.)portion.4.2.5.2 The minimum length of the specimen insert shall be 18.0 mm (0.56(0.71 in.) unless the conditions stipulated in 4.2.5.3are fulfilled.4.2.5.3 ThisThe dimensional requirement of 18 mm (0.71 in.) is based on Cha
27、rpy impact specimens tested on the upper shelf(where the plastic zone is maximum)largest) and fabricated with the stud welding reconstitution technique (where heat input andHAZ sizes are maximum).largest). Reconstituted specimens tested in the lower transition range or on the lower shelf in accordan
28、cewith Test Methods E23 and reconstituted precracked specimens tested in accordance with Test MethodMethods E1820 or E1921will have much smaller plastic zones. Other reconstitution techniques, such as electron beam welding, produce HAZs smaller thanstud welding. Therefore, this dimensional requireme
29、nt may be relaxed, if it can be experimentally or analytically shown that theplastic deformation zone in subsequent testing will not extend into the heat affected zones produced by reconstitution and therequirement of 4.4.1 is met (see Fig. 1). Test programs have shown acceptable Charpy results usin
30、g shorter inserts (7-8-910).4.2.6 Many weld specimens contain base material and HAZ. Therefore, care shall be taken such that the heat-affected zone ofan original weld is not contained in the central test section of the reconstituted specimen (see Fig. 1). HAZ specimens can be usedNOTEANo plastic de
31、formation from previous testing is permitted in the central test section.Temperature during welding in the 10-mm (0.39-in.) central test section shallnot exceed the irradiation temperature.FIG. 1 Schematic of a Reconstituted Charpy SpecimenE1253 132as an additional source of weld or base material fo
32、r inserts. In an inhomogeneous specimen insert, which contains base or weldmaterial and HAZ, only the target test material shall be contained in the central 10 mm (0.40 in.) 10-mm (0.39-in.) portion.4.3 FixturingThe fixture design will depend upon the type of welding process chosen for the welding o
33、peration.Asuccessfuldesign will maintain dimensional control, minimize heat input to the central test section, and satisfy design constraints associatedwith remote handling.4.4 Heat Input:4.4.1 To preclude irradiation damage annealing, heat input during welding shall be controlled such that no part
34、of the volumeof the central 10-mm (0.40-in.)(0.39-in.) portion of the reconstituted Charpy-sized specimen exceeds the prior metal irradiationtemperature at any time during welding (see Fig. 1). This requirement can be relaxed if it can be shown that the plastic deformationzone in subsequent testing
35、will not extend past the zone where irradiation temperature is exceeded.4.4.2 To demonstrate that the temperature requirement of 4.4.1 is met for a given selection of welding parameters, temperaturerecords shall be made daily, using thermocouples, during welding a set of Charpy-sized specimens. Such
36、 a demonstration ispreferably made on dummy inserts with thermocouples that are welded or soldered in the mid-thickness of the dummy insert. Ifsurface thermocouples are used, then a surface-to-center temperature correction must be made and the basis of the correctiondocumented. A comprehensive overv
37、iew of the important issues in temperature measurements can be found in Ref (1011).4.4.3 Thermocouples used in maximum temperature determination shall be calibrated in accordance with Test Method E220.4.5 Dimensional RequirementsDimensional control of reconstituted specimens shall be in accordance w
38、ith the subsequent-corresponding test method (Test Method E23, E1820, or E1921). If the user of this guide is unable to produce specimens that meetthe applicable test method dimensional requirements, then the user shall justify using specimens with dimensions exceeding thetest method requirements. A
39、ll deviations from the test method shall be documented and reported with the data. Ref (67) describesa study on the effects of some dimensional deviations.4.6 Safety PrecautionsThe reconstitution procedures generally involve handling irradiated specimen materials, and the userof this guide is respon
40、sible for establishing appropriate safety practices, which isare outside the scope of this guide.5. Qualification of Reconstitution Technique5.1 The welding process and fixture design shall be qualified prior to reconstituting specimens of interest, using materials ofknown impact properties. It shal
41、l be demonstrated during qualification that the following acceptance criteria have been achieved:5.1.1 The temperature of the central 10-mm (0.40-in.)(0.39-in.) portion of the specimen shall not exceed, at any time during thewelding process, a temperature that affects its metallurgical condition unl
42、ess it can be shown that the plastic deformation zone insubsequent testing will not extend past the zone where the metallurgical condition has been affected. In the case of irradiatedspecimens, the prior irradiation temperature must not be exceeded in the central 10-mm (0.39-in.) portion of the spec
43、imen.5.1.2 The welding procedure shall routinely produce weld quality such that fracture is at the notch of the reconstituted specimenand not in the reconstitution weldment. Examples of a weld qualification methodology can be found in Ref (1112).5.1.3 The reconstitution technique shall yield propert
44、ies (41-J and 68-J transition temperaturetemperatures and upper shelfenergy or reference temperature, To, or fracture toughness, as appropriate) equivalent to those of original testing.obtained from theoriginal tests. It is recommended that the reconstituted specimens for technique qualification be
45、tested at temperatures identical tothe original test temperatures so that data can be directly compared.5.1.4 The material used for reconstitution qualification shall be selected such that the properties of this material encompass aresimilar to the properties of the material of interest.6. Documenta
46、tion6.1 Specimen Reconstitution Record:6.1.1 Test material, test material tensile strength or hardness, origin, location, and orientation.6.1.2 Reconstituted specimen identity.6.1.3 Irradiation temperature and fast neutron fluence (E 1.0 MeV).6.1.4 Welding process parameters.6.1.5 Extension tab mate
47、rial and tensile strength or hardness.6.1.6 Statement of conformance with dimensional control to the subsequentcorresponding test method (Test Method E23, E1820or E1921).6.2 Additional DocumentationThe following information shall be available by reference to a suitable document.6.2.1 Process Qualifi
48、cation Information:6.2.1.1 Identities and nominal impact energies or KfractureJc toughness of the qualification specimens.6.2.1.2 Test temperature of the qualification specimens.6.2.1.3 Impact energy, lateral expansion, and fracture appearance, or KfractureJc, toughness, of the qualification specime
49、ns asappropriate.6.2.1.4 Comparison of original and reconstituted Charpy transition curves or comparison of the reference temperatures of theoriginal and reconstituted specimens.E1253 1336.2.2 Heat Input Monitoring:6.2.2.1 Type of temperature measurement equipment.6.2.2.2 Number of temperature measurements and locations.6.2.2.3 Details of temperature recording during the welding cycles.6.2.2.4 Precision and bias of the temperature measuring system.6.2.2.5 Fixturing details.6.2.3 Welding Procedure.Procedure:6.2.3.1 Specific welding parameters, such as current, voltage, type of
