1、Designation: E 10 08American Association State Highwayand Transportation Officials StandardAASHTO No.: T7086Standard Test Method forBrinell Hardness of Metallic Materials1This standard is issued under the fixed designation E 10; the number immediately following the designation indicates the year of
2、originaladoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of
3、 Defense.1. Scope1.1 This test method covers the determination of the Brinellhardness of metallic materials by the Brinell indentationhardness principle. This standard provides the requirements fora Brinell testing machine and the procedures for performingBrinell hardness tests.1.2 This standard inc
4、ludes additional requirements in fourannexes: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 nonmandatory
5、 information in anappendix 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, theforce levels were specified in units of kilogram
6、s-force (kgf).Although this standard specifies the unit of force in theInternational System of Units (SI) as the Newton (N), becauseof the historical precedent and continued common usage of kgfunits, force values in kgf units are provided for information andmuch of the discussion in this standard re
7、fers to forces in kgfunits.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations p
8、rior to use.2. Referenced Documents2.1 ASTM Standards:2E29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE74 Practice of Calibration of Force-Measuring Instru-ments for Verifying the Force Indication of Testing Ma-chinesE 140 Hardness Conversion Tables
9、 for Metals RelationshipAmong Brinell Hardness, Vickers Hardness, RockwellHardness, Superficial Hardness, Knoop Hardness, andScleroscope HardnessE 384 Test Method for Microindentation Hardness of Ma-terials2.2 American Bearings Manufacturer Association Stan-dard:ABMA 10-1989 Metal Balls32.3 ISO Stan
10、dards:ISO/IEC 17011 Conformity AssessmentGeneral Require-ments for Accreditation Bodies Accrediting ConformityAssessment Bodies4ISO/IEC 17025 General Requirements for the Competenceof Calibration and Testing43. Terminology and Equations3.1 Definitions:3.1.1 calibrationdetermination of the values of
11、the sig-nificant parameters by comparison with values indicated by areference instrument or by a set of reference standards.3.1.2 verificationchecking or testing to assure conform-ance with the specification.3.1.3 standardizationto bring in conformance with aknown standard through verification or ca
12、libration.3.1.4 Brinell hardness testan indentation hardness testusing a verified machine to force an indenter (tungsten carbideball with diameter D), under specified conditions, into thesurface of the material under test. The diameter of the resultingindentation d is measured after removal of the f
13、orce.3.1.5 Brinell hardness numbera number, which is propor-tional to the quotient obtained by dividing the test force by thecurved surface area of the indentation which is assumed to bespherical and of the diameter of the ball.1This test method is under the jurisdiction of ASTM Committee E28 onMech
14、anical Testing and is the direct responsibility of Subcommittee E28.06 onIndentation Hardness Testing.Current edition approved Dec. 1, 2008. Published January 2009. Originallyapproved in 1924. Last previous edition approved in 2007 as E 10 07a.2For referenced ASTM standards, visit the ASTM website,
15、www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Bearing Manufacturers Association (ABMA), 2025M Street, NW, Suite 800, Washington, DC 20036.
16、4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.1.6 Brinell hardness scalea designation that identifiest
17、he specific combination of ball diameter and applied forceused to perform the Brinell hardness test.3.1.7 Brinell hardness testing machinea Brinell hardnessmachine used for general testing purposes.3.1.8 Brinell hardness standardizing machinea Brinellhardness machine used for the standardization of
18、Brinellhardness test blocks. The standardizing machine differs from aregular Brinell hardness testing machine by having tightertolerances on certain parameters.3.1.9 force-diameter ratioa number calculated as the ratioof the test force in kgf to the square of the indenter balldiameter in mm (see Tab
19、le 1).3.2 Equations:3.2.1 The Brinell hardness number is calculated as:HBW 52FkgfpDD =D2 d2!(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 repeatability R in the performance of a Brinellhardness
20、machine at each hardness level, under the particularverification conditions, is estimated by the range of diametermeasurements of n indentations made on a standardized testblock as part of a performance verification, defined as:R 5 dmax dmin(2)where:dmax= mean diameter of the largest measured indent
21、ation,anddmin= mean diameter of the smallest measured indenta-tion.3.2.3 The average H of a set of n Brinell hardness measure-ment values H1, H2, ., Hnis calculated as:H 5H11 H21 . 1 Hnn(3)3.2.4 The error E in the performance of a Brinell hardnessmachine at each hardness level is determined as:E 5 H
22、 HSTD(4)where:H (Eq 3) = average of n hardness tests H1, H2, ., Hnmadeon a standardized test block as part of aperformance verification, andHSTD= certified average hardness value of the stan-dardized test block.3.2.5 The mean diameter of an indentation d is calculatedas:d 5d11 d21 . 1 dnn(5)Where:d1
23、, 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 indentationsis calculated as:d 5d1 1 d2 1 . 1 dNN(6)where:d1,d2, . dN = mean indentation diameters in mm, andN = number of indentations (see Annex A4).4. Signifi
24、cance and Use4.1 The Brinell hardness test is an indentation hardness testthat can provide useful information about metallic materials.This information may correlate to tensile strength, wear resis-tance, ductility, or other physical characteristics of metallicmaterials, and may be useful in quality
25、 control and selection ofmaterials.4.2 Brinell hardness tests are considered satisfactory foracceptance testing of commercial shipments, and have beenused extensively in industry for this purpose.4.3 Brinell hardness testing at a specific location on a partmay not represent the physical characterist
26、ics of the whole partor end product.5. Principles of Test and Apparatus5.1 Brinell Hardness Test PrincipleThe general principleof the Brinell indentation hardness test consists of two steps(see Fig. 1).5.1.1 Step 1The indenter is brought into contact with thetest specimen in a direction perpendicula
27、r to the surface, andthe test force F is applied. The test force is held for a specifieddwell time and then removed.TABLE 1 Symbols and DesignationsSymbol DesignationD Diameter of the ball, mmF Test force, NFkgfTest force, kgfFkgf51gn3 Fwhere gnis the acceleration due to gravity.gn= 9.80665 kgf/Nd M
28、ean diameter of the indentation, mmd 5d11 d21 . 1 dnnwhere d1+ d2+ . + dnare the measured indentationdiameters in mm, and n is the number of diametermeasurements.h Depth of the indentation, mmh 5D =D2 d22Force-Diameterratio5FkgfD2HBW Brinell hardness5Test ForceSurface area of indentation52Fkgfp D D
29、=D2 d2!E100825.1.2 Step 2The diameter of the indentation is measuredin at least two directions perpendicular to each other. TheBrinell hardness value is derived from the mean of the diametermeasurements.5.2 Brinell Testing MachineEquipment for Brinell hard-ness testing usually consists of a testing
30、machine, whichsupports the test specimen and applies an indenting force to aball in contact with the specimen, and a system for measuringthe mean diameter of the indentation in accordance with theBrinell hardness test principle. The design of the testingmachine shall be such that no rocking or later
31、al movement ofthe indenter or specimen occurs while the force is beingapplied. The design of the testing machine shall ensure that theforce to the indenter is applied smoothly and without impactforces. Precautions shall be taken to prevent a momentary hightest force caused by the inertia of the syst
32、em, hydraulic systemovershoot, etc.5.2.1 See the Equipment Manufacturers Instruction Manualfor a description of the machines characteristics, limitations,and respective operating procedures.5.2.2 AnvilsAn anvil, or specimen support, should beused that is suitable for the specimen to be tested. The s
33、eatingand supporting surfaces of all anvils should be clean and freeof foreign material. Typically, anvils need only be replaced ifthey fail to support the test surface perpendicular to theindenter, or they are deemed unsafe.5.2.3 IndentersIndenters for the Brinell hardness testshall be tungsten car
34、bide balls of four allowed diameters (1,2.5, 5 and 10 mm). Indenters shall meet the requirementsdefined in Annex A3.5.2.4 Oil, dirt, or other foreign materials shall not beallowed to accumulate on the indenter, as this will affect thetest results.5.2.5 Measurement DeviceThe measurement device usedfo
35、r the measurement of the diameter of Brinell indentationsmay be an integral part of the hardness machine or a separatestand-alone instrument. The allowable measurement devicesare classified into two types. The Type A device includesmicroscopes having movable measuring lines with some typeof indicato
36、r or computerized measuring system, or an imageanalysis system. The Type B device is a hand-held microscope(usually 203 or 403) with fixed measuring lines.5.2.5.1 Type A DeviceThe acceptable minimum resolutionfor a Type A device shall be as given in Table 2.5.2.5.2 Type B DeviceThe acceptable maximu
37、m spacingbetween the graduated lines of Type B devices shall be as givenin Table 2. Type B devices shall not be used for measuringindentations made with 2.5 mm and 1 mm ball indenters.5.3 VerificationBrinell testing machines and indentationmeasurement devices shall be verified periodically in accor-
38、dance with Annex A1.5.4 Test BlocksTest blocks meeting the requirements ofAnnex A4 shall be used to verify the testing machine inaccordance with Annex A1.5.5 Brinell Hardness ScalesThe combinations of indent-ers and test forces define the Brinell hardness scales. Thestandard Brinell hardness scales
39、and test forces are given inTable 3, corresponding to force-diameter ratios (see Table 1)of1, 1.25, 2.5, 5, 10 and 30. Brinell hardness values should bedetermined and reported in accordance with one of thesestandard scales. Other scales using non-standard test forcesmay be used by special agreement.
40、 Examples of other scalesand the corresponding force-diameter ratio (in parentheses) areHBW 10/750 (7.5), HBW 10/2000 (20), HBW 10/2500 (25),HBW 5/187.5 (7.5), and HBW 5/500 (20).5.6 Calculation of the Brinell Hardness NumberTheBrinell hardness number shall be calculated from the meanFIG. 1 Principl
41、e of TestTABLE 2 Resolution and Graduation Spacing of IndentationMeasuring DevicesType A Type BBall DiametermmMinimumIndicator ResolutionmmMaximumGraduation Spacingmm10 0.0100 0.1005 0.0050 0.0502.5 0.0025 1 0.0010 TABLE 3 Test Conditions and Recommended Hardness RangeBrinellHardnessScaleBallDiamete
42、rDmmForce-DiameterRatioANominal Value ofTest Force, FRecommendedHardness RangeHBWN kgfHBW 10/3000 10 30 29420 3000 95.5 to 650HBW 10/1500 10 15 14710 1500 47.7 to 327HBW 10/1000 10 10 9807 1000 31.8 to 218HBW 10/500 10 5 4903 500 15.9 to 109HBW 10/250 10 2.5 2452 250 7.96 to 54.5HBW 10/125 10 1.25 1
43、226 125 3.98 to 27.2HBW 10/100 10 1 980.7 100 3.18 to 21.8HBW 5/750 5 30 7355 750 95.5 to 650HBW 5/250 5 10 2452 250 31.8 to 218HBW 5/125 5 5 1226 125 15.9 to 109HBW 5/62.5 5 2.5 612.9 62.5 7.96 to 54.5HBW 5/31.25 5 1.25 306.5 31.25 3.98 to 27.2HBW 5/25 5 1 245.2 25 3.18 to 21.8HBW 2.5/187.5 2.5 30
44、1839 187.5 95.5 to 650HBW 2.5/62.5 2.5 10 612.9 62.5 31.8 to 218HBW 2.5/31.25 2.5 5 306.5 31.25 15.9 to 109HBW 2.5/15.625 2.5 2.5 153.2 15.625 7.96 to 54.5HBW 2.5/7.8125 2.5 1.25 76.61 7.8125 3.98 to 27.2HBW 2.5/6.25 2.5 1 61.29 6.25 3.18 to 21.8HBW 1/30 1 30 294.2 30 95.5 to 650HBW 1/10 1 10 98.07
45、10 31.8 to 218HBW 1/5 1 5 49.03 5 15.9 to 109HBW 1/2.5 1 2.5 24.52 2.5 7.96 to 54.5HBW 1/1.25 1 1.25 12.26 1.25 3.98 to 27.2HBW 1/1 1 1 9.807 1 3.18 to 21.8ASee Table 1.E10083diameter d of the indentation using Eq 1 or from the valuesgiven in Appendix X1.5.6.1 Brinell hardness values shall not be de
46、signated by anumber alone because it is necessary to indicate which indenterand which force has been employed in making the test (seeTable 3). Brinell hardness numbers shall be followed by thesymbol HBW, and be supplemented by an index indicating thetest conditions in the following order:5.6.1.1 Dia
47、meter of the ball, mm,5.6.1.2 Avalue representing the test force, kgf, (see Table 3)and,5.6.1.3 The applied force dwell time, s, if other than 10 s to15 s.5.6.2 The only exception to the above requirement is for theHBW 10/3000 scale when a 10 s to 15 s dwell time is used.Only in the case of this one
48、 Brinell hardness scale may thedesignation be reported simply as HBW.5.6.3 Examples:220 HBW = Brinell hardness of 220 determined with a ball of 10 mm diameterand with a test force of 29.42 kN (3000 kgf) applied for 10 s to 15 s350 HBW 5/750 = Brinell hardness of 350 determined with a ball of 5 mmdia
49、meter and with a test force of 7.355 kN (750 kgf) applied for 10 s to 15 s600 HBW 1/30/20 = Brinell hardness of 600 determined with a ball of 1 mmdiameter and with a test force of 294.2 N (30 kgf) applied for 20 s6. Test Piece6.1 There is no standard shape or size for a Brinell testspecimen. The test piece on which the indentation is madeshould conform to the following:6.1.1 ThicknessThe thickness of the specimen tested shallbe such that no bulge or other marking showing the effect ofthe test force appears on the side of the piece opposite
