1、Designation: E10 15aE10 17 American Association State Highwayand Transportation Officials StandardAASHTO No.: T7086Standard Test Method forBrinell Hardness of Metallic Materials1This standard is issued under the fixed designation E10; the number immediately following the designation indicates the ye
2、ar of originaladoption or, in the case of revision, the 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. Depart
3、ment of Defense.1. Scope*1.1 This test method covers the determination of the Brinell hardness of metallic materials by the Brinell indentation hardnessprinciple. This standard provides the requirements for a Brinell testing machine and the procedures for performing Brinell hardnesstests.1.2 This st
4、andard includes additional requirements in four annexes:Verification of Brinell Hardness Testing Machines Annex A1Brinell Hardness Standardizing Machines Annex A2Standardization of Brinell Hardness Indenters Annex A3Standardization of Brinell Hardness Test Blocks Annex A41.3 This standard includes n
5、onmandatory information in an appendix which relates to the Brinell hardness test:Table of Brinell Hardness Numbers Appendix X1Examples of Procedures for DeterminingBrinell Hardness UncertaintyAppendix X21.4 At the time the Brinell hardness test was developed, the force levels were specified in unit
6、s of kilograms-force (kgf).Although this standard specifies the unit of force in the International System of Units (SI) as the Newton (N), because of thehistorical precedent and continued common usage of kgf units, force values in kgf units are provided for information and muchof the discussion in t
7、his standard refers to forces in kgf units.1.5 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 to establish appropriate safety and health practices and determine the applicability of regulator
8、ylimitations prior to use.1.6 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 Organizatio
9、n Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2E29 Practice for Using Significant Digits in Test Data to Determine Conformance with SpecificationsE74 Practice of Calibration of Force-Measuring Instruments for Verifying the Force Indication of Testing Machine
10、sE140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness,Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb HardnessE384 Test Method for Microindentation Hardness of Materials2.2 American Bearings Manufacturer Association
11、Standard:ABMA 10-1989 Metal Balls31 This test method is under the jurisdiction of ASTM Committee E28 on Mechanical Testing and is the direct responsibility of Subcommittee E28.06 on IndentationHardness Testing.Current edition approved Dec. 1, 2015April 1, 2017. Published January 2016May 2017. Origin
12、ally approved in 1924. Last previous edition approved in 2015 asE10 15.E10 15a. DOI: 10.1520/E0010-15A.10.1520/E0010-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer
13、to the standards Document Summary page on the ASTM website.3 Available from American Bearing Manufacturers Association (ABMA), 2025 M Street, NW, Suite 800, Washington, DC 20036, http:/www.americanbearings.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM
14、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 cases only the current versionof the standard as published by
15、 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 States12.3 ISO Standards:ISO/IEC 17011 Conformity AssessmentGeneral Requirements
16、 for Accreditation Bodies Accrediting Conformity AssessmentBodies4ISO/IEC 17025 General Requirements for the Competence of Calibration and Testing43. Terminology and Equations3.1 Definitions:3.1.1 calibrationdetermination of the values of the significant parameters by comparison with values indicate
17、d by a referenceinstrument or by a set of reference standards.3.1.2 verificationchecking or testing to assure conformance with the specification.3.1.3 standardizationto bring in conformance with a known standard through verification or calibration.3.1.4 Brinell hardness testan indentation hardness t
18、est using a verified machine to force an indenter (tungsten carbide ball withdiameter D), under specified conditions, into the surface of the material under test. The diameter of the resulting indentation d ismeasured after removal of the force.3.1.5 Brinell hardness numbera number, which is proport
19、ional to the quotient obtained by dividing the test force by the curvedsurface area of the indentation which is assumed to be spherical and of the diameter of the ball.3.1.6 Brinell hardness scalea designation that identifies the specific combination of ball diameter and applied force used toperform
20、 the Brinell hardness test.3.1.7 Brinell hardness testing machinea Brinell hardness machine used for general testing purposes.3.1.8 Brinell hardness standardizing machinea Brinell hardness machine used for the standardization of Brinell hardness testblocks. The standardizing machine differs from a r
21、egular Brinell hardness testing machine by having tighter tolerances on certainparameters.3.1.9 force-diameter ratioa number calculated as the ratio of the test force in kgf to the square of the indenter ball diameterin mm (see Table 1).3.2 Equations:3.2.1 The Brinell hardness number is calculated a
22、s:HBW5 2FkgfpiDD 2=D22d2!(1)where:Fkgf = test force in kgf,D = diameter of the indenter ball in mm, andd = measured mean diameter of the indentation in mm (see Table 1).3.2.2 The average mean diameter d of a set of n indentations is calculated as:d 5d11d211dnn (2)where:d1, d2, . dn = diameter values
23、 of the indentations in mm, andn = number of indentations (see Annex A4).3.2.3 The repeatability R in the performance of a Brinell hardness machine at each hardness level, under the particularverification conditions, is estimated by the percent range of diameter measurementsvalues of n indentations
24、made on a standardizedtest block as part of a performance verification, relative to the average of the n measured diameter values d (Eq 2), defined as:R 5dmax2dmin (3)R 51003dmax2dmind(3)where:dmax = mean diameter of the largest measured indentation, anddmin = mean diameter of the smallest measured
25、indentation.dmax = diameter value of the largest measured indentation4 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http:/www.ansi.org.E10 172dmin = diameter value of the smallest measured indentation, andd(Eq 2) = average of the diamete
26、r values of the n indentations.3.2.4 The averageH of a set of n Brinell hardness measurement values H1, H2, ., Hn is calculated as:H5H11H211Hnn (4)3.2.5 The error E in the performance of a Brinell hardness machine at each hardness level is determined level, under theparticular verification condition
27、s, is estimated by the percent error of the average of n indentation measurements made on astandardized test block as part of a performance verification relative to the certified average hardness value of the standardized testblock, defined as:E 5H2HSTD (5)E 51003S?H2HSTD?HSTD D (5)where:H (Eq3)= av
28、erage of n hardness tests H1, H2, ., Hn made on a standardized test block as part of a performance verification,andTABLE 1 Symbols and DesignationsSymbol DesignationD Diameter of the ball, mmF Test force, NFkgf Test force, kgfFkgf5 1gn3Fwhere gn is the acceleration due to gravity.gn = 9.80665 kgf/Ng
29、n = 9.80665 N/kgfd Mean diameter of the indentation, mmd Diameter value of the indentation, mmd5d11d211dnnd5ds1d1ds2d11dsNdNwhere d1 + d2 + . + dn are the measured indentationdiameters in mm, and n is the number of diameter mea-surements.where d(1), d(2) . d(N) are the measured indentationdiameters
30、in mm, and N is the number of diameter mea-surements (typically 2).h Depth of the indentation, mmh5D2D22d22Force-Diameterratio5FkgfD2HBW Brinell hardness5 Test ForceSurface area of indentation5 2FkgfpiD sD2D22d2dE10 173HSTD = certified average hardness value of the standardized test block.H (Eq 4) =
31、 average of n hardness tests H1, H2, ., Hn made on a standardized test block as part of a performance verification,HSTD = certified average hardness value of the standardized test block, and|H 2HSTD| = absolute value (non-negative value without regard to its sign) of the difference between H and HST
32、D.3.2.5 The mean diameter of an indentationd is calculated as:d 5d11d211dnn (5)Where:d1, d2, ., dn = measured indentation diameters in mm, andn = the number of diameter measurements.3.2.6 The average mean diameter d of a set of indentations is calculated as:d 5d11d211dNN (6)where:d1, d2, . dN = mean
33、 indentation diameters in mm, andN = number of indentations (see Annex A4).4. Significance and Use4.1 The Brinell hardness test is an indentation hardness test that can provide useful information about metallic materials. Thisinformation may correlate to tensile strength, wear resistance, ductility,
34、 or other physical characteristics of metallic materials, andmay be useful in quality control and selection of materials.4.2 Brinell hardness tests are considered satisfactory for acceptance testing of commercial shipments, and have been usedextensively in industry for this purpose.4.3 Brinell hardn
35、ess testing at a specific location on a part may not represent the physical characteristics of the whole part orend product.5. Principles of Test and Apparatus5.1 Brinell Hardness Test PrincipleThe general principle of the Brinell indentation hardness test consists of two steps (see Fig.1).5.1.1 Ste
36、p 1The indenter is brought into contact with the test specimen in a direction perpendicular to the surface, and the testforce F is applied. The test force is held for a specified dwell time and then removed.5.1.2 Step 2The diameter of the indentation is measured in at least two directions perpendicu
37、lar to each other. The Brinellhardness value is derived from the mean of the diameter measurements.5.2 Brinell Testing MachineEquipment for Brinell hardness testing usually consists of a testing machine, which supports thetest specimen and applies an indenting force to a ball in contact with the spe
38、cimen, and a system for measuring the mean diameterof the indentation in accordance with the Brinell hardness test principle. The design of the testing machine shall be such that norocking or lateral movement of the indenter or specimen occurs while the force is being applied. The design of the test
39、ing machineshall ensure that the force to the indenter is applied smoothly and without impact forces. Precautions shall be taken to prevent amomentary high test force caused by the inertia of the system, hydraulic system overshoot, etc.5.2.1 See the Equipment Manufacturers Instruction Manual for a d
40、escription of the machines characteristics, limitations, andrespective operating procedures.FIG. 1 Principle of TestE10 1745.2.2 AnvilsAn anvil, or specimen support, should be used that is suitable for the specimen to be tested. The seating andsupporting surfaces of all anvils should be clean and fr
41、ee of foreign material. Typically, anvils need only be replaced if they failto support the test surface perpendicular to the indenter, or they are deemed unsafe.5.2.3 IndentersIndenters for the Brinell hardness test shall be tungsten carbide balls of four allowed diameters (1, 2.5, 5 and10 mm). Inde
42、nters shall meet the requirements defined in Annex A3.5.2.4 Oil, dirt, or other foreign materials shall not be allowed to accumulate on the indenter, as this will affect the test results.5.2.5 Measurement DeviceThe measurement device used for the measurement of the diameter of Brinell indentations m
43、ay bean integral part of the hardness machine or a separate stand-alone instrument. The allowable measurement devices are classifiedinto two types. The Type A device includes microscopes having movable measuring lines with some type of indicator orcomputerized measuring system, or an image analysis
44、system. The Type B device is a hand-held microscope (usually 20 or 40)with fixed measuring lines.5.2.5.1 Type A DeviceThe acceptable minimum resolution for a Type A device shall be as given in Table 2.5.2.5.2 Type B DeviceThe acceptable maximum spacing between the graduated lines of Type B devices s
45、hall be as given inTable 2. Type B devices shall not be used for measuring indentations made with 2.5 mm and 1 mm ball indenters.5.3 VerificationBrinell testing machines and indentation measurement devices shall be verified periodically in accordancewith Annex A1.5.4 Test BlocksTest blocks meeting t
46、he requirements of Annex A4 shall be used to verify the testing machine in accordancewith Annex A1.5.5 Brinell Hardness ScalesThe combinations of indenters and test forces define the Brinell hardness scales. The standardBrinell hardness scales and test forces are given in Table 3, corresponding to f
47、orce-diameter ratios (see Table 1) of 1, 1.25, 2.5,5, 10 and 30. Brinell hardness values should be determined and reported in accordance with one of these standard scales. Otherscales using non-standard test forces may be used by special agreement. Examples of other scales and the correspondingforce
48、-diameter ratio (in parentheses) are HBW 10/750 (7.5), HBW 10/2000 (20), HBW 10/2500 (25), HBW 5/187.5 (7.5), andHBW 5/500 (20).5.6 Calculation of the Brinell Hardness NumberThe Brinell hardness number shall be calculated from the mean diameter dof the indentation using Eq 1 or from the values given
49、 in Appendix X1.5.6.1 Brinell hardness values shall not be designated by a number alone because it is necessary to indicate which indenter andwhich force has been employed in making the test (see Table 3). Brinell hardness numbers shall be followed by the symbol HBW,and be supplemented by an index indicating the test conditions in the following order:5.6.1.1 Diameter of the ball, mm,5.6.1.2 A value representing the test force, kgf, (see Table 3) and,5.6.1.3 The applied force dwell time, s, if other than 10 s to 15 s.5.6.2
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