ASTM E18-2018 Standard Test Methods for Rockwell Hardness of Metallic Materials《金属材料洛氏硬度的标准试验方法》.pdf

1、Designation: E18 171E18 18 An American National StandardStandard Test Methods forRockwell Hardness of Metallic Materials1,2This standard is issued under the fixed designation E18; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the

2、 year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S. Department of Defense.1 NOTEA2.8.1.8 was editorially correcte

3、d in August 2017.1. Scope*1.1 These test methods cover the determination of the Rockwell hardness and the Rockwell superficial hardness of metallicmaterials by the Rockwell indentation hardness principle.This standard provides the requirements for Rockwell hardness machinesand the procedures for per

4、forming Rockwell hardness tests.1.2 This test method includes requirements for the use of portable Rockwell hardness testing machines that measure Rockwellhardness by the Rockwell hardness test principle and can meet all the requirements of this test method, including the direct andindirect verifica

5、tions of the testing machine. Portable Rockwell hardness testing machines that cannot meet the direct verificationrequirements and can only be verified by indirect verification requirements are covered in Test Method E110.1.3 This standard includes additional requirements in the following annexes:Ve

6、rification of Rockwell Hardness Testing Machines Annex A1Rockwell Hardness Standardizing Machines Annex A2Standardization of Rockwell Indenters Annex A3Standardization of Rockwell Hardness Test Blocks Annex A4Guidelines for Determining the Minimum Thickness of aTest PieceAnnex A5Hardness Value Corre

7、ctions When Testing on ConvexCylindrical SurfacesAnnex A61.4 This standard includes nonmandatory information in the following appendixes whichthat relates to the Rockwell hardnesstest.List of ASTM Standards Giving Hardness ValuesCorrespondingto Tensile StrengthAppendix X1Examples of Procedures for D

8、etermining RockwellHardness UncertaintyAppendix X21.5 UnitsAt the time the Rockwell hardness test was developed, the force levels were specified in units of kilograms-force(kgf) and the indenter ball diameters were specified in units of inches (in.). This standard specifies the units of force and le

9、ngthin the International System of Units (SI); that is, force in Newtons (N) and length in millimeters (mm). However, because of thehistorical precedent and continued common usage, force values in kgf units and ball diameters in inch units are provided forinformation and much of the discussion in th

10、is standard refers to these units.1.6 The test principles, testing procedures, and verification procedures are essentially identical for both the Rockwell andRockwell superficial hardness tests. The significant differences between the two tests are that the test forces are smaller for theRockwell su

11、perficial test than for the Rockwell test. The same type and size indenters may be used for either test, depending onthe scale being employed. Accordingly, throughout this standard, the term Rockwell will imply both Rockwell and Rockwellsuperficial unless stated otherwise.1.7 This standard does not

12、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 safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1 These test me

13、thods are under the jurisdiction of ASTM Committee E28 on Mechanical Testing and are the direct responsibility of Subcommittee E28.06 on IndentationHardness Testing.Current edition approved July 1, 2017July 1, 2018. Published July 2017October 2018. Originally approved in 1932. Last previous edition

14、approved in 20162017 asE18 16.E18 171. DOI: 10.1520/E0018-17E0110.1520/E0018-182 In this test method, the term Rockwell refers to an internationally recognized type of indentation hardness test as defined in Section 3, and not to the hardness testingequipment of a particular manufacturer.This docume

15、nt 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. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as ap

16、propriate. In all cases 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 standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United S

17、tates11.8 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers

18、 to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3A370 Test Methods and Definitions for Mechanical Testing of Steel ProductsA623 Specification for Tin Mill Products, General RequirementsA623M Specification for Tin Mill Products, General Requirements MetricA883 Test Method for Ferr

19、imagnetic Resonance Linewidth and Gyromagnetic Ratio of Nonmetallic Magnetic MaterialsA956 Test Method for Leeb Hardness Testing of Steel ProductsA1038 Test Method for Portable Hardness Testing by the Ultrasonic Contact Impedance MethodB19 Specification for Cartridge Brass Sheet, Strip, Plate, Bar,

20、and DisksB36/B36M Specification for Brass Plate, Sheet, Strip, And Rolled BarB96/B96M Specification for Copper-SiliconAlloy Plate, Sheet, Strip, and Rolled Bar for General Purposes and Pressure VesselsB103/B103M Specification for Phosphor Bronze Plate, Sheet, Strip, and Rolled BarB121/B121M Specific

21、ation for Leaded Brass Plate, Sheet, Strip, and Rolled BarB122/B122M Specification for Copper-Nickel-Tin Alloy, Copper-Nickel-Zinc Alloy (Nickel Silver), and Copper-Nickel AlloyPlate, Sheet, Strip, and Rolled BarB130 Specification for Commercial Bronze Strip for Bullet JacketsB134/B134M Specificatio

22、n for Brass WireB152/B152M Specification for Copper Sheet, Strip, Plate, and Rolled BarB370 Specification for Copper Sheet and Strip for Building ConstructionB647 Test Method for Indentation Hardness of Aluminum Alloys by Means of a Webster Hardness GageE29 Practice for Using Significant Digits in T

23、est Data to Determine Conformance with SpecificationsE92 Test Methods for Vickers Hardness and Knoop Hardness of Metallic MaterialsE110 Test Method for Rockwell and Brinell Hardness of Metallic Materials by Portable Hardness TestersE140 Hardness Conversion Tables for Metals Relationship Among Brinel

24、l Hardness, Vickers Hardness, Rockwell Hardness,Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb HardnessE384 Test Method for Microindentation Hardness of MaterialsE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method2.2 American Bearin

25、gs Manufacturer Association Standard:ABMA 10-1989 Metal Balls42.3 ISO Standards:ISO 6508-1 Metallic MaterialsRockwell Hardness TestPart 1: Test Method (scales A, B, C, D, E, F, G, H, K, N, T)5ISO/IEC 17011 Conformity AssessmentGeneral Requirements for Accreditation Bodies Accrediting Conformity Asse

26、ssmentBodies5ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories52.4 Society of Automotive Engineers (SAE) Standard:SAE J417 Hardness Tests and Hardness Number Conversions63. Terminology and Equations3.1 Definitions:3.1.1 calibrationdetermination of the valu

27、es of the significant parameters by comparison with values indicated by a referenceinstrument or by a set of reference standards.3.1.2 verificationchecking or testing to assure conformance with the specification.3.1.2 standardizationto bring in conformance to a known standard through verification or

28、 calibration.3.1.3 verificationchecking or testing to assure conformance with the specification.3.1.4 Rockwell hardness testan indentation hardness test using a verified machine to force a diamond spheroconical indenteror tungsten carbide (or steel) ball indenter, under specified conditions, into th

29、e surface of the material under test, and to measurethe difference in depth of the indentation as the force on the indenter is increased from a specified preliminary test force to aspecified total test force and then returned to the preliminary test force.3 For referencedASTM standards, visit theAST

30、M website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from American Bearing Manufacturers Association (ABMA), 2025 M Street, NW, Suite 800, Washing

31、ton, DC 20036.5 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.6 Available from Society of Automotive Engineers (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.org.E18 1823.1.5 Rockwell superficial

32、hardness testsame as the Rockwell hardness test except that smaller preliminary and total testforces are used with a shorter depth scale.3.1.6 Rockwell hardness numbera number derived from the net increase in the depth of indentation as the force on an indenteris increased from a specified prelimina

33、ry test force to a specified total test force and then returned to the preliminary test force.3.1.7 Rockwell hardness machinea machine capable of performing a Rockwell hardness test and/or a Rockwell superficialhardness test and displaying the resulting Rockwell hardness number.3.1.7.1 Rockwell hard

34、ness testing machinea Rockwell hardness machine used for general testing purposes.3.1.7.2 Rockwell hardness standardizing machinea Rockwell hardness machine used for the standardization of Rockwellhardness indenters, and for the standardization of Rockwell hardness test blocks. The standardizing mac

35、hine differs from a regularRockwell hardness testing machine by having tighter tolerances on certain parameters.3.1.7.3 portable Rockwell hardness testing machinea Rockwell hardness testing machine that is designed to be transported,carried, set up, and operated by the users, and that measures Rockw

36、ell hardness by the Rockwell indentation hardness testprinciple.3.1.7.4 movable Rockwell hardness testing machinea Rockwell hardness testing machine that is designed to be moved todifferent locations on a moveable frame, table or similar support that is integral to the testing machine (for example,

37、securely fixedto a rolling table), or a Rockwell hardness testing machine that is designed to move into testing position prior to a test, (forexample, securely fixed to a moving support arm), and has been previously verified to ensure that such a move will not affect thehardness result.3.2 Equations

38、:3.2.1 The averageH of a set of n hardness measurements H1, H2, , Hn is calculated as:H5H11H211Hnn (1)3.2.2 The error E in the performance of a Rockwell hardness machine at each hardness level, relative to a standardized scale,is determined as:E 5H2HSTD (2)where:H = average of n hardness measurement

39、s H1, H2, , Hn made on a standardized test block as part of a performanceverification, andHSTD = certified average hardness value of the standardized test block.3.2.3 The repeatability R in the performance of a Rockwell hardness machine at each hardness level, under the particularverification condit

40、ions, is estimated by the range of n hardness measurements made on a standardized test block as part of aperformance verification, defined as:R 5Hmax2Hmin (3)where:Hmax = highest hardness value, andHmin = lowest hardness value.4. Significance and Use4.1 The Rockwell hardness test is an empirical ind

41、entation hardness test that can provide useful information about metallicmaterials. This information may correlate to tensile strength, wear resistance, ductility, and other physical characteristics ofmetallic materials, and may be useful in quality control and selection of materials.4.2 Rockwell ha

42、rdness tests are considered satisfactory for acceptance testing of commercial shipments, and have been usedextensively in industry for this purpose.4.3 Rockwell hardness testing at a specific location on a part may not represent the physical characteristics of the whole partor end product.4.4 Adhere

43、nce to this standard test method provides traceability to national Rockwell hardness standards except as statedotherwise.5. Principles of Test and Apparatus5.1 Rockwell Hardness Test PrincipleThe general principle of the Rockwell indentation hardness test is illustrated in Fig. 1.The test is divided

44、 into three steps of force application and removal.E18 183Step 1The indenter is brought into contact with the test specimen, and the preliminary test force F0 is applied. After holdingthe preliminary test force for a specified dwell time, the baseline depth of indentation is measured.Step 2The force

45、 on the indenter is increased at a controlled rate by the additional test force F1 to achieve the total test forceF. The total test force is held for a specified dwell time.Step 3The additional test force is removed, returning to the preliminary test force. After holding the preliminary test forcefo

46、r a specified dwell time, the final depth of indentation is measured. The Rockwell hardness value is derived from the differenceh in the final and baseline indentation depths while under the preliminary test force. The preliminary test force is removed and theindenter is removed from the test specim

47、en.5.1.1 There are two general classifications of the Rockwell test: the Rockwell hardness test and the Rockwell superficialhardness test. The significant difference between the two test classifications is in the test forces that are used. For the Rockwellhardness test, the preliminary test force is

48、 10 kgf (98 N) and the total test forces are 60 kgf (589 N), 100 kgf (981 N), and 150kgf (1471 N). For the Rockwell superficial hardness test, the preliminary test force is 3 kgf (29 N) and the total test forces are 15kgf (147 N), 30 kgf (294 N), and 45 kgf (441 N).5.1.2 Indenters for the Rockwell h

49、ardness test include a diamond spheroconical indenter and tungsten carbide ball indenters ofspecified diameters.5.1.2.1 Steel indenter balls may be used only for testing thin sheet tin mill products specified in Specifications A623 and A623Musing the HR15Tand HR30Tscales with a diamond spot anvil.Testing of this product may give significantly differing results usinga tungsten carbide ball as compared to historical test data using a steel ball.NOTE 1Previous editions of this standard have stated that the steel ball was the standard type of Ro