StandardTestMethodsandDefinitionsfor MechanicalTestingofSteelProducts
This standard is isued under the fxed designation A370; the mumber immediately folwing the designatie indicates the year of original adoption ot in the case of revisin the year of last revision. A number in parentheses indicates the year of last reapproval. A suescript epiln () indicates an editrial chne since the last revisin or reappl.
Tis l m fr mh ir e US. Dr f De.
1. Scope*
for the mechanical testing of steels stainless steels and related 1.1 These test methods² cover procedures and definitionsto determine properties required in the product specifications. alloys. The various mechanical tests herein described are usedVariations in testing methods are to be avoided and standardmethods of testing are to be followed to obtain reproducible and parable results. In those cases in which the testingthese general procedures the product specification testing requirements for certain products are unique or at variance withrequirements shall control.
as standard. The values given in parentheses are mathematical 1.4 The values stated in inch-pound units are to be regardedand are not considered standard. conversions to SI units that are provided for information only
1.5 When these test methods are referenced in a metricproduct specification the yield and tensile values may be determined in inch-pound (ksi) units then converted into SI(MPa units. The elongation determined in inch-pound gauge lengths of 2 or 8 in. may be reported in SI unit gauge lengthsof 50 or 200 mm respectively as applicable. Conversely whenthese test methods are referenced in an inch-pound product specification the yield and tensile values may be determined inSI units then converted into inch-pound units. The elongation determined in SI unit gauge lengths of 50 or 200 mm may bereported in inch-pound gauge lengths of 2 or 8 in. respectively as applicable.
1.2 The following mechanical tests are described:
SectionsBend Tension 7 to 14 15Hardness Brinell 16 17Impact Portable Rockwell 20 to 30 18 19Keywonds 32
1.5.1 The specimen used to determine the original unitsmust conform to the applicable tolerances of the original unit system given in the dimension table not that of the convertedtolerance dimensions.
1.3 Annexes covering details peculiar to certain productsare appended to these test methods as follows:
being hard conversions when this is not a dual standard. The user is Nome 1This is due to the specimen SI dimensions and tolerancesdirected to Test Methods A1058 if the tests are required in SI units.
Bar Products Annex A1 AnnexFasteners Tubular Products Round Wire Products Annex A4 Annex A2 Annex A3Converting Percentage Elongstion of Round Specimens to Significance of Notched-Bar Impact Testing Arnnex A6 Annex A5Testing Muli-Wire Strand Equivalents for Flat Specimens Annex Ag Annex A7Methods for Testing Steel Reinforcing Bars Rounding of Test Data Annex A9
1.6 Attention is directed to ISO/IEC 17025 when there maybe a need for information on criteria for evaluation of testing laboratories.
1.7 Tuis standard does nor purport to address all of theresponsibiliry of the user of this standard to establish appro- safery concerns if any associated with its use. lr is thepriote sofery health and environmental practices and deter-mine the applicability of regulatory lisnitations prior to use.
1.8 Tuis international standard was developed in accor-dance with internationally recognized principles on stondord- ization established in the Decision on Principles for theDevelopment of International Stondords Guides and Reco- mendations issued by rhe Worid Trade Organization TechunicalBarriers to Trade (TBT) Commiltee.
2. Referenced Documents
3.1.1 For definitions of terms pertaining to mechanicaltesting of steel products not otherwise listed in this section reference should be made to Terminology E6 and Terminology A941.
2.1 ASTM Standards:3A623 Specification for Tin Mill Products General Require-A623M Specification for Tin Mill Products General Re- mentsA833 Test Method for Indentation Hardness of MetallicA941 Terminology Relating to Steel Stainless Steel Related Materials by Comparison Hardness TestersA956/A956M Test Methxd for Leeb Hardness Testing of Alloys and FerroalloysSteel ProductsA1038 Test Method for Portable Hardness Testing by the Ultrasonic Contact Impedance MethodA1058 Test Methods for Mechanical Testing of Steel Products-MetricA1061/A1061M Test Methods for Testing Multi-Wire SteelE4 Practices for Force Verification of Testing Machines Prestressing StrandE6 Terminology Relating to Methods of Mechanical Testing E8/E8M Test Methods for Tension Testing of Metallic Ma-terialsE10 Test Method for Brinell Hardness of Metallic Materials E18 Test Methods for Rockwell Hardness of Metallic Ma-E23 Test Methods for Notched Bar Impact Testing of Me- terialsE29 Practice for Using Signicant Digits in Test Data to tallic MaterialsDetermine Conformance with SpecificationsE83 Practice for Verification and Classification of Exten- someter SystemsEl10 Test Method for Rockwell and Brinell Hardness of Metallic Materials by Portable Hardness TestersE190 Test Method for Guided Bend Test for Ductility ofE290 Test Methods for Bend Testing of Material for Ducetil- s2.2 ASME Document:^ ityASME Boiler and Pressure Vessel Code. Section VIIl.2.3 ISO Standard:s Division I Part UG-8ISO/IEC 17025 General Requirements for the Competenceof Testing and Calibration Laboratories
3.2 Definitions of Terms Specific to This Standard:
3.2.1 longirudinal rest nunless specifically definedotherwise signifies that the lengthwise axis of the specimen is parallel to the direction of the greatest extension of the steelduring rolling or forging.
3.2.1.1 DiscassionThe stress applied to a longitudinaltension test specimen is in the direction of the greatestextension and the axis of the fold of a longitudinal bend test specimen is at right angles to the direction of greatest extension(see Fig. 1 Fig. 2a and Fig. 2b).
3.2.2 radial rest unless specifically defined otherwise signifies that the lengthwise axis of the specimen is perpen-dicular to the axis of the product and coincident with one of the radi of a circle drawn with a point on the axis of the productas a center (see Fig. 2a).
otherwise signifies that the lengthwise axis of the specimen 3.2.3 rangential rest nunless specifically definedperpendicular to a plane containing the axis of the product and tangent to a circle drawn with a point on the axis of theproductas a center (see Fig. 2a Fig. 2b Fig. 2c and Fig. 2d).
the transition temperature is the temperature at which the 3.2.4 rcnsition temperanure nfor specification puposes designated material test value equals or exceeds a specified minimum test value.
3.2.4.1 Discussion-Some of the many definitions of tran-temperature at which the specimen exhibits 100 % fibrous sition temperature currently being used are: (7) the lowestnd ）uddeq ospu ues fracture (2) the temperature where the fracture shows a 50 %corresponding to the energy value 50 % of the difference
3. Terminology
3.1 Definitions:
FIG. 1 Relation of Test Coupons and Test Specimens to RollingDirection or Extension (Applicable to General Wrought Products)
FIG. 2 Location of Longitudinal Tension Test Specimens in Rings Cut From Tubular Products
between values obtained at 100 and 0 % fibrous fracture and(4) the temperature corresponding to a specific energy value.
3.2.5.1 Discassion-The stress applied to a transverse ten-sion test specimen is at right angles to the greatest extension and the axis of the fold of a transverse bend test specimen isparallel to the greatest extension (see Fig. 1).
3.2.5 ransverse test nunless specifically definedotherwise signifies that the lengthwise axis of the specimen is right angles to the direction of the greatest extension of thesteel during rolling or forging.
3.3 Definition of Terms Specific to the Procedure for Useand Control of Heat-cycle Simularion (See Arnex A9):
inhomogeneity anisotropic structure natural aging of selectalloys further processing not included in the specification sampling limitations and measuring equipment calibration uncertainty. There is statistical variation in all aspects ofare expected. An understanding of possible reasons for devia- mechanical testing and variations in test results from prior teststion from specified or expected test values should be applied in interpretation of test results.
ceived from a forging essentially identical to the production 3.3.1 muster chcr n-a record of the heat treatment re-forgings that it will represent.
3.3.1.1 DiscassionIt is a chart of time and temperatureshowing the output from thermocouples imbedded in the forging at the designated test immersion and test location orlocations.
5. General Precautions
gram the simulator unit. 3.3.2 program chart nthe metallized sheet used to pro-
5.1 Certain methods of fabrication such as bending.forming and welding or operations involving heating may affect the properties of the material under test. Therefore theproduct specifications cover the stage of manufacture at which mechanical testing is to be performed. The properties shown bytesting prior to fabrication may not necessarily be representa-tive of the product after it has been pletely fabricated.
chart are manually transferred to the program chart. 3.3.2.1 DiscassionTime-temperature data from the master
3.3.3 simarlator chart na record of the heat treatment that a test specimen had received in the simulator unit.
3.3.3.1 Discassion-It is a chart of time and temperatureand can be pared directly to the master chart for accuracyof duplication.
5.2 Improperly machined specimens should be discardedand other specimens substituted.
3.3.4 simlotor cycle one continuous heat treatment of aset of specimens in the simulator unit.
specimen develops flaws the retest provision of the applicable 5.3 Flaws in the specimen may also affect results. If any testproduct specification shall govern.
3.3.4.1 DiscussionThe cycle includes heating fromambient holding at temperature and cooling. For example apo suds jo ns e po qounb pe ose pe be one cycle; a simulated temper of the same specimens wouldbe another cycle.
5.4 If any test specimen fails because of mechanical reasonsdsdonodo us jo an se nspreparation it may be discarded and another specimen taken.
6. Orientation of Test Specimens
4. Significance and Use
6.1 The terms “longitudinal test” and “transverse test" areused only in material specifications for wrought products andare not applicable to castings. When such reference is made to a test coupon or test specimen see Section 3 for terms anddefinitions.
determine the specified mechanical properties of steel stainless 4.1 The primary use of these test methods is testing tosteel and related alloy products for the evaluation of confor- mance of such products to a material specification under thejurisdiction of ASTM Committee A01 and its submittees asdesignated by a purchaser in a purchase order or contract.
TENSION TEST
4.1.1 These test methods may be and are used by otherpurpose of conformance testing. ASTM Committees and other standards writing bodies for the
7.Deseription
7.1The tension test related to the mechanical testing of steelproducts subjects a machined or full-section specimen of the material under examination to a measured load sufficient tocause rupture. The resulting properties sought are defined in Terminology E6.
frequency specimen location and orientation reporting 4.1.2 The material condition at the time of testing samplingrequirements and other test parameters are contained in thespecification for the particular product form.
7.2 In general the testing equipment and methods are givenin Test Methods E8/E8M. However there are certain excep- tions to Test Methods E8/E8M practices in the testing of steel and these are covered in these test methods.
tional test methods not described herein; in such cases the 4.1.3 Some material specifications require the use of addi-or by reference to another appropriate test method standard. required test method is described in that material specification
8. Testing Apparatus and Operations
4.2 These test methods are also suitable to be used fortesting of steel stainless steel and related alloy materials for Ssn oe uoou se qns sasodnd oby the purchaser or evaluation of ponents after serviceexposure.
ing systems mechanical (screw power) and hydraulic. These 8.1 Loading SystemsThere are two general types of load-differ chiefly in the variability of the rate of load application. The older screw power machines are limited to a small numberof fixed free running crosshead speeds. Some modern screwpower machines and all hydraulic machines permit stepless variation throughout the range of speeds.
4.2.1 As with any mechanical testing deviations from eitherspecification limits or expected as-manufactured properties can occur for valid reasons besides deficiency of the originallimited to: subsequent service degradation from environmental as-fabricated product. These reasons include but are notexposure (for example temperature corrosion); static or cyclicservice stress effects mechanically-induced damage material
operating condition used only in the proper loading range and 8.2 The tension testing machine shall be maintained in goodcalibrated periodically in accordance with the latest revision ofPractices E4.
NotE 2Many machines are equipped with stress-strain recorders forautographic ploting of stress-strain curves. It should be noted that some reconders have a lad measuring ponent entirely separate from theload indicator of the testing machine. Such recorders are calibrated separately.
8.3 LoudingIt is the function of the gripping or holdingdevice of the testing machine to transmit the load from the heads of the machine to the specimen under test. The essentialrequirement is that the load shall be transmitted axially. This implies that the centers of the action of the grips shall be inalignment insofar as practicable with the axis of the specimenat the beginning and during the test and that bending or twisting be held to a minimum. For specimens with a reducedsection gripping of the specimen shall be restricted to the grip section. In the case of certain sections tested in full size permissible. nonaxial loading is unavoidable and in such cases shall be
8.4 Speed of Tesring-The speed of testing shall not begreater than that at which load and strain readings can be made sn opds od u expressed: (/) in terms of free running crosshead speed (rate ofmovement of the crosshead of the testing machine when not under load) (2) in terms of rate of separation of the two headsof the testing machine under load (3) in terms of rate ofstressing the specimen or (4) in terms of rate of straining the specimen. The following limitations on the speed of testing areremended as adequate for most steel products:
control of rate) should not be performed using load control as this mode e ) sr dopa usn s sof testing will result in acceleration of the crosshead upon yielding and elevation of the measured yield strength.
one half the specified yield point or yield strength. When this 8.4.1 Any convenient speed of testing may be used up topoint is reached the free-running rate of separation of thecrossheads shall be adjusted so as not to exceed s in. per min per inch of reduced section or the distance between the gripsfor test specimens not having reduced sections. This speed shall be maintained through the yield point or yield strength. Indetermining the tensile strength the fre-running rate ofseparation of the heads shall not exceed in. per min per inch of reduced section or the distance between the grips for testspecimens not having reduced sections. In any event the minimum speed of testing shall not be less than Vio thestrength and tensile strength. specified maximum rates for determining yield point or yield
8.4.2 It shall be permissible to set the speed of the testingmachine by adjusting the free running crosshead speed to the above specified values inasmuch as the rate of separation ofheads under load at these machine settings is less than the specified values of free running crosshead speed.
8.4.3 As an altermative if the machine is equipped with adevice to indicate the rate of loading the speed of the machine from half the specified yield point or yield strength through theyield point or yield strength may be adjusted so that the rate ofHowever the minimum rate of stressing shall not be less than10 000 psi (70 MPa)/min.
9. Test Specimen Parameters
9.1 SelectionTest coupons shall be selected in accordancewith the applicable product specifications.
9.1.1 Wroughr SteelsWrought steel products are usuallysize permits and the service justifies it testing is in the tested in the longitudinal direction but in some cases wheretransverse radial or tangential directions (see Figs. I and 2).
tension testing is usually provided by allowing extensions or 9.1.2 Forged SteelsFor open die forgings the metal forprolongations on one or both ends of the forgings either on all or a representative number as provided by the applicablemid-radius. Certain product specifications permit the use of a product specifications. Test specimens are normally taken atrepresentative bar or the destruction of a production part fortest purposes. For ring or disk-like forgings test metal is provided by increasing the diameter thickness or length f thforging. Upset disk or ring forgings which are worked or extended by forging in a direction perpendicular to the axis ofthe forging usually have their principal extension along concentric circles and for such forgings tangential tensionspecimens are obtained from extra metal on the periphery orend of the forging. For some forgings such as rotors radial tension tests are required. In such cases the specimens are cutor trepanned from specified locations.
9.2 Size and Tolerances-Test specimens shall be (I) thefull cross section of material or (2) machined to the form anddimensions shown in Figs. 36. The selection of size and type of specimen is prescribed by the applicable product specifica-tion. Full cross section specimens shall be tested in 8-in. (200 mm) gauge length unless otherwise specified in theproduct specification.
extracted by any convenient method taking care to remove all 9.3 Procarerent of Tesr SpecimensSpecimens shall bedistorted cold-worked or heat-affected areas from the edges ofthe section used in evaluating the material. Specimens usually have a reduced cross section at mid-length to ensure uniformdistribution of the stress over the cross section and localize the zone of fracture.
9.4 Aging of Tesr SpecimensUnless otherwise specified itshall be permissible to age tension test specimens. The time- temperature cycle employed must be such that the effects ofprevious processing will not be materially changed. It may be acplished by aging at room temperature 24 to 48 h or inshorter time at moderately elevated temperatures by boiling in water heating in oil or in an oven.
9.5 Measurement of Dimensions of Test Specimens:
forms of specimens are shown in Fig. 3. To determine the 9.5.1 Stcncdard Rectangular Tension Tesr SpecimensThesecross-sectional area the center width dimension shall bemm) gauge length specimen and 0.001 in. (0.025 mm) for the measured to the nearest 0.005 in. (0.13 mm) for the 8-in. (2002-in. (50 mm) gauge length specimen in Fig. 3. The center thickness dimension shall be measured to the nearest 0.001 in.for both specimens.
9.5.2 Standard Round Tension Test SpecimensTheseforms of specimens are shown in Fig. 4 and Fig. 5. Todetermine the cross-sectional area the diameter shall be
