1、Designation: E 643 09Standard Test Method forBall Punch Deformation of Metallic Sheet Material1This standard is issued under the fixed designation E 643; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.INTRODUCTIONThe ball punch deformation test is used for evaluating the ductility of metallic sheet materials. Thetest involves biaxial stretching o
3、f a constrained test specimen. Ideally, no draw-in of flange metal fromunder the hold-down occurs. The sheet metal test specimen is bulged at a specified rate until the loaddrops or until either necking or fracture occurs; the test is then terminated. Ball punch (penetrator)movement to drop in-load
4、or necking or fracture is the test result. It is known that test results may varywith hold-down force, lubrication, and criterion for determining the end point of the test.1. Scope1.1 This test method covers the procedure for conductingthe ball punch deformation test for metallic sheet materialsinte
5、nded for forming applications. The test applies to speci-mens with thicknesses between 0.008 and 0.080 in. (0.20 and2.00 mm).1.2 The values stated in inchpound units are to be regardedas the standard.NOTE 1The ball punch deformation test is intended to replace theOlsen cup test by standardizing many
6、 of the test parameters thatpreviously have been left to the discretion of the testing laboratory.NOTE 2The modified Erichsen test has been standardized in Europe.The main differences between the ball punch deformation test and theErichsen test are the diameters of the penetrator and the dies. Erich
7、sen cupheights are given in SI units.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 This standard does not purport to address al
8、l 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 prior to use.2. Referenced Documents2.1 ASTM Standards:2E 177 Practice for U
9、se of the Terms Precision and Bias inASTM Test MethodsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method2.2 National Institute of Standards and Technology Docu-ment:3NIST Handbook 91 Experimental Statistics3. Terminology3.1 Definitions of Terms Specific
10、 to This Standard:3.1.1 cup height, the height of the formed cup at the endpoint of the test.4. Significance and Use4.1 The ball punch deformation test is widely used toevaluate and compare the formability of metallic sheet mate-rials. Biaxial stretching is the predominant mode of deforma-tion occur
11、ring during the test and, therefore, the results aremost often used to rate or compare materials that are to beformed mainly by stretching. However, precise correlationsbetween the cup height as determined by this test and the1This test method is under the jurisdiction of ASTM Committee E28 onMechan
12、ical Testing and is the direct responsibility of Subcommittee E28.02 onDuctility and Formability.Current edition approved June 1, 2009. Published June 2009. Originallypublished in 1978. Last previous edition approved in 2000 as E 643 -84(2000)which was withdrawn March 2009 and reinstated in June 200
13、9.2For referenced ASTM standards, visit the ASTM website, 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 National Institute of Standards and Technol
14、ogy (NIST), 100Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http:/www.nist.gov.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.formability of a sheet material under production conditionshave not been established.4.2 It is reco
15、gnized that the cup heights for specimens fromthe same sample may vary with differences in magnitude ofhold-down force, lubrication, and method of end point deter-mination. The procedures described in Sections 5, 7.1, and 7.3will minimize these variations.5. Apparatus5.1 Cupping Machines (Fig. 1)Any
16、 machine used for ballpunch deformation tests shall be equipped to hold the specimenwith a minimum force of 2200 lbf (9800 N). It shall have aspherical-ended penetrator capable of forcing the central por-tion of the specimen through the die until the end point of thetest occurs (see 7.3).5.1.1 Varia
17、tion in hold-down force is a source of variation incup height. For machines not equipped to measure the hold-down force, the magnitude of the force should be established.5.1.2 The magnitude of the hold-down force shall be suchthat no appreciable draw-in occurs.5.1.3 The machine shall be provided wit
18、h a displacementindicator to measure cup height.5.2 Displacement IndicatorThe displacement indicatorshall monitor the ball penetrator movement and the scale shallbe graduated such that displacement can be measured to withinat least 6 0.0025 in. (when using indicators reading in SI units,the displace
19、ment shall be measured to within at least 6 0.05mm).5.3 Tooling:FIG. 1 Ball Punch Deformation Test ToolingE6430925.3.1 The penetrator shall be sufficiently rigid so as not to bedeformed or to turn or move laterally during the test. Its headshall be spherical and have a diameter of 0.875 6 0.002 in.(
20、22.226 0.05 mm), and only this spherical portion of thepenetrator shall contact the specimen. The penetrator shallmove along the axial centerline of the top and bottom dies. Itshall be clean and free from oxide build-up, corrosion, dirt, etc.5.3.2 The surface of the top die in contact with the tests
21、pecimen shall be plane and parallel to the surface of thebottom die. Both surfaces shall be clean and free from oxidebuild-up, corrosion, dirt, etc.5.3.3 The surface finish of the penetrator and top die incontact with the specimen shall not exceed 160 in. (0.004mm) when based on maximum distance pea
22、k-to-peak.5.3.4 The spherical portion of the penetrator shall have ahardness not less than 62 HRC. The working surfaces of the topand bottom dies shall have a hardness of 56 HRC or higher.6. Test Specimens6.1 Number of TestsA minimum of three tests shall beperformed. When greater precision is requir
23、ed, see Section 9for determining the number of tests to be performed.6.2 Specimen SizeSpecimen blanks may be either circularor rectangular. The minimum width (or diameter) shall be 3.5in. (90 mm). When evaluating rectangular strip, the cups shallnot be closer than 3.0 in. (75 mm) from center to cent
24、er, and thecenter of any cup shall not be within 1.5 in. (38 mm) of the endof the strip.NOTE 3The minimum specimen width may be 2.5 in. (65 mm) formachines unable to accommodate larger width specimens.6.3 Specimen ThicknessThis method applies to thick-nesses between 0.008 and 0.080 in. (0.20 and 2.0
25、 mm). Theappropriate top dies are shown below. When thicknesses lessthan 0.020 in. are tested, it is recommended that the top diehave self-leveling capability. When thicknesses greater than0.080 in. are tested, agreement regarding the hold-downpressure necessary to prevent draw-in and the appropriat
26、e topdie opening shall be made between the supplier and the user.Specimen Thickness,in. (mm)Top Die Opening,in. (mm)0.060 (1.5) or less 1.000 (25.40)over 0.060 to 0.080 (1.5 to 2.0) 1.125 (28.58)7. Procedure7.1 Lubrication:7.1.1 The cup height is strongly affected by the choice oflubricant or whethe
27、r lubrication is employed at all. Studieshave shown that variation in lubrication influences the straindistribution and the state of strain in the material beingstretched over the punch. The cup height obtained underwell-lubricated conditions will be significantly greater than thatobtained under poo
28、rly lubricated conditions.7.1.1.1 Use a commercially available petroleum jelly as thelubricant.7.1.1.2 Do not mechanically or chemically alter the speci-men surface, which shall be representative of the material assupplied.7.1.2 Lubricate only the punch. A thin coat of lubricant issufficient. In ord
29、er to decrease the possibility of any relativemovement (that is, “draw-in”) of the specimen with respect tothe die surfaces, do not lubricate the dies or test specimen.7.1.3 Other systems of lubrication and specimen preparationmay be used as agreed upon between the supplier and the user.7.2 Test Spe
30、ed:7.2.1 The speed of the penetrator shall be between 0.2 and1.0 in./min (0.08 and 0.40 mm/s).7.2.2 Near the end of the test, the speed may be reduced tothe lower limit in order to more accurately determine the endpoint.7.3 End Point of Test:7.3.1 The preferred method for determining the end pointsh
31、all be by the drop-in load on the specimen. In general, thisindicates the onset of necking in the dome.7.3.1.1 Some test machines may not be equipped with a loadindicator. In this case, the end point shall be either visiblenecking or fracture of the test specimen in the dome.7.3.1.2 Do not consider
32、the test results valid for normalreporting when fracture occurs in the hold-down area (basefailures).7.3.1.3 If the drop-in-load method is used and the machinehas a pressure switch unit, set the switch at minimum timedelay.7.3.1.4 Report the method used to determine the end pointwith the test result
33、s.7.3.2 Ball Punch Deformation Cup Height:7.3.2.1 The cup height is the penetrator displacement asmeasured by the indicator in thousandths of an inch (orhundredths of a millimetre) at the end point of the test.7.3.2.2 Set the penetrator displacement indicator to readzero at the start of test. The st
34、art of test is when the penetrator,under test conditions, makes contact with the specimen.NOTE 4The test results may be affected by specimen thinning if thetests are performed on a machine that uses an indicator in contact with thetest piece.8. Report8.1 The report shall include the following:8.1.1
35、Identification of the material.8.1.2 Thickness of the material.8.1.3 Method of end point determination.8.1.4 Number of tests.8.1.5 Type of lubricant, if other than specified.8.1.6 Average value and range (or standard deviation) ofcup heights.8.1.7 Average of maximum loads (if known).8.1.8 Method of
36、hold-downconstant or proportional.8.1.9 Hold-down force (if known).9. Precision and Bias9.1 The precision of this test method is based on aninterlaboratory study of E 643, Standard Test Method forMeasurement of Ball Punch Deformation of Metallic SheetMaterial, conducted in 2008. Each of six laborato
37、ries testedfive different materials. Every “test result” represents anindividual determination. Each laboratory reported three repli-cate test results for the analyses. Practice E 691 was followedE643093for the design and analysis of the data; the details are given inASTM Research Report No. E28-104
38、1.49.1.1 Repeatability limit (r)Two test results obtainedwithin one laboratory shall be judged not equivalent if theydiffer by more than the “r” value for that material; “r”istheinterval representing the critical difference between two testresults for the same material, obtained by the same operator
39、using the same equipment on the same day in the samelaboratory.9.1.1.1 Repeatability limits are listed in Table 1, Table 2,and Table 3.9.1.2 Reproducibility limit (R)Two test results shall bejudged not equivalent if they differ by more than the “R” valuefor that material; “R” is the interval represe
40、nting the criticaldifference between two test results for the same material,obtained by different operators using different equipment indifferent laboratories.9.1.2.1 Reproducibility limits are listed in Table 1, Table 2,and Table 3.9.1.3 The above terms (repeatability limit and reproducibil-ity lim
41、it) are used as specified in Practice E 177.9.1.4 Any judgment in accordance with statements 9.1.1and 9.1.2 would have an approximate 95% probability of beingcorrect.9.2 BiasAt the time of the study, there was no acceptedreference material suitable for determining the bias for this testmethod, there
42、fore no statement on bias is being made.9.3 The precision statement was determined through statis-tical examination of 270 results, from six laboratories, on fivematerials. The materials were described as the following:Material A: 0.021 in. Cold rolled steel (uncoated)Material B: 0.034 in. Hot-dip g
43、alvanized steelMaterial C: 0.036 in. Hot-dip galvannealed steelMaterial D: 0.038 in. Cold rolled steel (uncoated)Material E: 0.079 in. Hot-dip galvannealed steel4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:E28-1041.TABLE 1 Da
44、y 1 (thousandths of an in.)Material AverageARepeatability Standard Deviation Reproducibility Standard Deviation Repeatability Limit Reproducibility LimitxSrSRrRA 426.22 2.95 30.98 8.27 86.75B 371.89 9.50 19.30 26.61 54.04C 434.33 5.73 24.04 16.03 67.30D 408.72 8.09 16.73 22.65 46.86E 581.00 10.60 25
45、.30 29.68 70.83AThe average of the laboratories calculated averages.TABLE 2 Day 2 (thousandths of an in.)Material AverageARepeatability Standard Deviation Reproducibility Standard Deviation Repeatability Limit Reproducibility LimitxSrSRrRA 426.61 2.37 28.79 6.63 80.61B 370.28 5.43 25.38 15.19 71.05C
46、 437.61 3.99 22.50 11.16 63.00D 408.39 4.05 21.14 11.34 59.19E 579.83 9.40 22.78 26.31 63.79AThe average of the laboratories calculated averages.TABLE 3 Day 3 (thousandths of an in.)Material AverageARepeatability Standard Deviation Reproducibility Standard Deviation Repeatability Limit Reproducibili
47、ty LimitxSrSRrRA 425.89 2.86 32.05 8.00 89.74B 376.44 8.83 17.55 24.74 49.15C 435.94 3.77 22.41 10.56 62.75D 408.06 7.62 17.67 21.33 49.47E 579.44 3.82 22.78 10.70 63.79AThe average of the laboratories calculated averages.E643094ASTM International takes no position respecting the validity of any pat
48、ent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision
49、 at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown belo
