1、Designation:A37011a Designation: A370 12Standard Test Methods and Definitions forMechanical Testing of Steel Products1This standard is issued under the fixed designation A370; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 These test methods2cover proced
3、ures and definitions for the mechanical testing of steels, stainless steels, and related alloys.The various mechanical tests herein described are used to determine properties required in the product specifications. Variationsin testing methods are to be avoided, and standard methods of testing are t
4、o be followed to obtain reproducible and comparableresults. In those cases in which the testing requirements for certain products are unique or at variance with these generalprocedures, the product specification testing requirements shall control.1.2 The following mechanical tests are described:Sect
5、ionsTension 5to13Bend 14Hardness 15Brinell 16Rockwell 17Portable 18Impact 19 to 28Keywords 291.3 Annexes covering details peculiar to certain products are appended to these test methods as follows:AnnexBar Products A1.1Tubular Products Annex A2Fasteners Annex A3Round Wire Products Annex A4Significan
6、ce of Notched-Bar Impact Testing Annex A5Converting Percentage Elongation of Round Specimens toEquivalents for Flat SpecimensAnnex A6Testing Multi-Wire Strand Annex A7Rounding of Test Data Annex A8Methods for Testing Steel Reinforcing Bars Annex A9Procedure for Use and Control of Heat-Cycle Simulati
7、on Annex A101.4 The values stated in inch-pound units are to be regarded as the standard.1.5 When this document is referenced in a metric product specification, the yield and tensile values may be determined ininch-pound (ksi) units then converted into SI (MPa) units. The elongation determined in in
8、ch-pound gauge lengths of 2 or 8 in.may be reported in SI unit gauge lengths of 50 or 200 mm, respectively, as applicable. Conversely, when this document isreferenced in an inch-pound product specification, the yield and tensile values may be determined in SI units then converted intoinch-pound unit
9、s. The elongation determined in SI unit gauge lengths of 50 or 200 mm may be reported in inch-pound gaugelengths of 2 or 8 in., respectively, as applicable.1.6 Attention is directed to ISO/IEC 17025 when there may be a need for information on criteria for evaluation of testinglaboratories.1.7 This s
10、tandard 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 to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1These test methods and def
11、initions are under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and are the direct responsibility ofSubcommittee A01.13 on Mechanical and Chemical Testing and Processing Methods of Steel Products and Processes.Current edition approved Nov.March 15, 2011.2012. P
12、ublished December 2011.March 2012. Originally approved in 1953. Last previous edition approvedin2011asA370 11a. DOI: 10.1520/A0370-11a.10.1520/A0370-12.2For ASME Boiler and Pressure Vessel Code applications see related Specification SA-370 in Section II of that Code.1This document is not an ASTM sta
13、ndard and is intended only to provide the user of an ASTM standard an indication of what changes have been made 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 cas
14、es only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.2. Referenced
15、Documents2.1 ASTM Standards:3A623 Specification for Tin Mill Products, General RequirementsA623M Specification for Tin Mill Products, General Requirements MetricA703/A703M Specification for Steel Castings, General Requirements, for Pressure-Containing PartsA781/A781M Specification for Castings, Stee
16、l and Alloy, Common Requirements, for General Industrial UseA833 Practice for Indentation Hardness of Metallic Materials by Comparison Hardness TestersE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE8/E8M Test Methods for Tension Testin
17、g of Metallic MaterialsE10 Test Method for Brinell Hardness of Metallic MaterialsE18 Test Methods for Rockwell Hardness of Metallic MaterialsE23 Test Methods for Notched Bar Impact Testing of Metallic MaterialsE29 Practice for Using Significant Digits in Test Data to Determine Conformance with Speci
18、ficationsE83 Practice for Verification and Classification of Extensometer SystemsE110 Test Method for Indentation Hardness of Metallic Materials by Portable Hardness TestersE190 Test Method for Guided Bend Test for Ductility of WeldsE290 Test Methods for Bend Testing of Material for Ductility2.2 ASM
19、E Document:4ASME Boiler and Pressure Vessel Code, Section VIII, Division I, Part UG-82.3 ISO Standard:5ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories3. General Precautions3.1 Certain methods of fabrication, such as bending, forming, and welding, or oper
20、ations involving heating, may affect theproperties of the material under test. Therefore, the product specifications cover the stage of manufacture at which mechanicaltesting is to be performed. The properties shown by testing prior to fabrication may not necessarily be representative of the product
21、after it has been completely fabricated.3.2 Improper machining or preparation of test specimens may give erroneous results. Care should be exercised to assure goodworkmanship in machining. Improperly machined specimens should be discarded and other specimens substituted.3.3 Flaws in the specimen may
22、 also affect results. If any test specimen develops flaws, the retest provision of the applicableproduct specification shall govern.3.4 If any test specimen fails because of mechanical reasons such as failure of testing equipment or improper specimenpreparation, it may be discarded and another speci
23、men taken.4. Orientation of Test Specimens4.1 The terms “longitudinal test” and “transverse test” are used only in material specifications for wrought products and are notapplicable to castings. When such reference is made to a test coupon or test specimen, the following definitions apply:4.1.1 Long
24、itudinal Test, unless specifically defined otherwise, signifies that the lengthwise axis of the specimen is parallel to thedirection of the greatest extension of the steel during rolling or forging. The stress applied to a longitudinal tension test specimenis in the direction of the greatest extensi
25、on, and the axis of the fold of a longitudinal bend test specimen is at right angles to thedirection of greatest extension (Fig. 1, Fig. 2a, and 2b).4.1.2 Transverse Test, unless specifically defined otherwise, signifies that the lengthwise axis of the specimen is at right anglesto the direction of
26、the greatest extension of the steel during rolling or forging. The stress applied to a transverse tension testspecimen is at right angles to the greatest extension, and the axis of the fold of a transverse bend test specimen is parallel to thegreatest extension (Fig. 1).4.2 The terms “radial test” a
27、nd “tangential test” are used in material specifications for some wrought circular products and arenot applicable to castings. When such reference is made to a test coupon or test specimen, the following definitions apply:4.2.1 Radial Test, unless specifically defined otherwise, signifies that the l
28、engthwise axis of the specimen is perpendicular to theaxis of the product and coincident with one of the radii of a circle drawn with a point on the axis of the product as a center (Fig.2a).4.2.2 Tangential Test, unless specifically defined otherwise, signifies that the lengthwise axis of the specim
29、en is perpendicularto a plane containing the axis of the product and tangent to a circle drawn with a point on the axis of the product as a center (Fig.2a, 2b, 2c, and 2d).3For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at serviceastm.org. For A
30、nnual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4Available from American Society of Mechanical Engineers (ASME), ASME International Headquarters, Three Park Ave., New York, NY 10016-5990.5Available from American National Standards Inst
31、itute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.A370 122TENSION TEST5. Description5.1 The tension test related to the mechanical testing of steel products subjects a machined or full-section specimen of thematerial under examination to a measured load sufficient to ca
32、use rupture. The resulting properties sought are defined inTerminology E6.5.2 In general, the testing equipment and methods are given in Test Methods E8/E8M. However, there are certain exceptionsto Test Methods E8/E8M practices in the testing of steel, and these are covered in these test methods.6.
33、Terminology6.1 For definitions of terms pertaining to tension testing, including tensile strength, yield point, yield strength, elongation, andreduction of area, reference should be made to Terminology E6.7. Testing Apparatus and Operations7.1 Loading SystemsThere are two general types of loading sy
34、stems, mechanical (screw power) and hydraulic. These differchiefly in the variability of the rate of load application. The older screw power machines are limited to a small number of fixedfree running crosshead speeds. Some modern screw power machines, and all hydraulic machines permit stepless vari
35、ationthroughout the range of speeds.7.2 The tension testing machine shall be maintained in good operating condition, used only in the proper loading range, andcalibrated periodically in accordance with the latest revision of Practices E4.NOTE 1Many machines are equipped with stress-strain recorders
36、for autographic plotting of stress-strain curves. It should be noted that somerecorders have a load measuring component entirely separate from the load indicator of the testing machine. Such recorders are calibrated separately.7.3 LoadingIt is the function of the gripping or holding device of the te
37、sting machine to transmit the load from the heads ofthe machine to the specimen under test. The essential requirement is that the load shall be transmitted axially. This implies thatthe centers of the action of the grips shall be in alignment, insofar as practicable, with the axis of the specimen at
38、 the beginningand during the test and that bending or twisting be held to a minimum. For specimens with a reduced section, gripping of thespecimen shall be restricted to the grip section. In the case of certain sections tested in full size, nonaxial loading is unavoidableand in such cases shall be p
39、ermissible.7.4 Speed of TestingThe speed of testing shall not be greater than that at which load and strain readings can be madeaccurately. In production testing, speed of testing is commonly expressed: (1) in terms of free running crosshead speed (rate ofmovement of the crosshead of the testing mac
40、hine when not under load), (2) in terms of rate of separation of the two heads of thetesting machine under load, (3) in terms of rate of stressing the specimen, or (4) in terms of rate of straining the specimen. Thefollowing limitations on the speed of testing are recommended as adequate for most st
41、eel products:NOTE 2Tension tests using closed-loop machines (with feedback control of rate) should not be performed using load control, as this mode of testingwill result in acceleration of the crosshead upon yielding and elevation of the measured yield strength.FIG. 1 The Relation of Test Coupons a
42、nd Test Specimens toRolling Direction or Extension (Applicable to General WroughtProducts)A370 1237.4.1 Any convenient speed of testing may be used up to one half the specified yield point or yield strength. When this pointis reached, the free-running rate of separation of the crossheads shall be ad
43、justed so as not to exceed116 in. per min per inch ofreduced section, or the distance between the grips for test specimens not having reduced sections. This speed shall be maintainedthrough the yield point or yield strength. In determining the tensile strength, the free-running rate of separation of
44、 the heads shallnot exceed12 in. per min per inch of reduced section, or the distance between the grips for test specimens not having reducedsections. In any event, the minimum speed of testing shall not be less than110 the specified maximum rates for determining yieldpoint or yield strength and ten
45、sile strength.7.4.2 It shall be permissible to set the speed of the testing machine by adjusting the free running crosshead speed to the abovespecified values, inasmuch as the rate of separation of heads under load at these machine settings is less than the specified valuesof free running crosshead
46、speed.7.4.3 As an alternative, if the machine is equipped with a device to indicate the rate of loading, the speed of the machine fromhalf the specified yield point or yield strength through the yield point or yield strength may be adjusted so that the rate of stressingdoes not exceed 100 000 psi (6
47、90 MPa)/min. However, the minimum rate of stressing shall not be less than 10 000 psi (70MPa)/min.8. Test Specimen Parameters8.1 SelectionTest coupons shall be selected in accordance with the applicable product specifications.FIG. 2 Location of Longitudinal Tension Test Specimens in Rings Cut from T
48、ubular ProductsA370 1248.1.1 Wrought SteelsWrought steel products are usually tested in the longitudinal direction, but in some cases, where sizepermits and the service justifies it, testing is in the transverse, radial, or tangential directions (see Fig. 1 and Fig. 2).8.1.2 Forged SteelsFor open di
49、e forgings, the metal for tension testing is usually provided by allowing extensions orprolongations on one or both ends of the forgings, either on all or a representative number as provided by the applicable productspecifications. Test specimens are normally taken at mid-radius. Certain product specifications permit the use of a representativebar or the destruction of a production part for test purposes. For ring or disk-like forgings test metal is provided by increasing thediameter, thickness, or length of the forging. Upset disk or ring forgings, which are work
