ASTM E643-84(1995)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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An American National Standard
Designation:E643–84 (Reapproved 1995)
Standard Test Method for
Ball Punch Deformation of Metallic Sheet Material
This standard is issued under the fixed designation E 643; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
The ball punch deformation test is used for evaluating the ductility of metallic sheet materials. The
test involves biaxial stretching of a constrained test specimen. Ideally, no draw-in of flange metal from
under the hold-down occurs. The sheet metal test specimen is bulged at a specified rate until the load
drops or until either necking or fracture occurs; the test is then terminated. Ball punch (penetrator)
movementtodropin-loadorneckingorfractureisthetestresult.Itisknownthattestresultsmayvary
with hold-down force, lubrication, and criterion for determining the end point of the test.
1. Scope Methods forAnalysis and Testing of Industrial Chemicals
2.2 National Institute of Standards and Technology Docu-
1.1 This test method covers the procedure for conducting
ment:
the ball punch deformation test for metallic sheet materials
NIST Handbook 91 Experimental Statistics
intended for forming applications. The test applies to speci-
mens with thicknesses between 0.008 and 0.080 in. (0.20 and
3. Terminology
2.00 mm).
3.1 Definitions of Terms Specific to This Standard:
1.2 The values stated in inch–pound units are to be regarded
3.1.1 cup height, the height of the formed cup at the end
as the standard.
point of the test.
NOTE 1—The ball punch deformation test is intended to replace the
Olsen cup test by standardizing many of the test parameters that
4. Significance and Use
previously have been left to the discretion of the testing laboratory.
4.1 The ball punch deformation test is widely used to
NOTE 2—The modified Erichsen test has been standardized in Europe.
evaluate and compare the formability of metallic sheet mate-
The main differences between the ball punch deformation test and the
rials. Biaxial stretching is the predominant mode of deforma-
Erichsen test are the diameters of the penetrator and the dies. Erichsen cup
heights are given in SI units. tion occurring during the test and, therefore, the results are
most often used to rate or compare materials that are to be
1.3 This standard does not purport to address all of the
formed mainly by stretching. However, precise correlations
safety concerns, if any, associated with its use. It is the
between the cup height as determined by this test and the
responsibility of the user of this standard to establish appro-
formability of a sheet material under production conditions
priate safety and health practices and determine the applica-
have not been established.
bility of regulatory limitations prior to use.
4.2 It is recognized that the cup heights for specimens from
2. Referenced Documents the same sample may vary with differences in magnitude of
hold-down force, lubrication, and method of end point deter-
2.1 ASTM Standards:
mination. The procedures described in Sections 5, 7.1, and 7.3
E 177 Practice for Use of the Terms Precision and Bias in
will minimize these variations.
ASTM Test Methods
E 180 Practice for Determining the Precision of ASTM
5. Apparatus
5.1 Cupping Machines (Fig. 1)—Any machine used for ball
punchdeformationtestsshallbeequippedtoholdthespecimen
This test method is under the jurisdiction of ASTM Committee E-28 on
with a minimum force of 2200 lbf (9800 N). It shall have a
Mechanical Testing, and is the direct responsibility of Subcommittee E28.02 on
Ductility and Flexure.
Current edition approved April 27, 1984. Published July 1984. Originally Annual Book of ASTM Standards, Vol 15.05.
published as E 643 – 78. Available from the Superintendent of Documents, U.S. Government Printing
Annual Book of ASTM Standards, Vol 14.02. Office, Washington, DC 20402.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E643–84 (1995)
FIG. 1 Ball Punch Deformation Test Tooling
spherical-ended penetrator capable of forcing the central por- be graduated such that displacement can be measured to within
tion of the specimen through the die until the end point of the atleast 60.0025in.(whenusingindicatorsreadinginSIunits,
test occurs (see 7.3). the displacement shall be measured to within at least 6 0.05
5.1.1 Variationinhold-downforceisasourceofvariationin mm).
cup height. For machines not equipped to measure the hold- 5.3 Tooling:
down force, the magnitude of the force should be established. 5.3.1 Thepenetratorshallbesufficientlyrigidsoasnottobe
5.1.2 The magnitude of the hold-down force shall be such deformed or to turn or move laterally during the test. Its head
that no appreciable draw-in occurs. shall be spherical and have a diameter of 0.875 6 0.002 in.
5.1.3 The machine shall be provided with a displacement (22.226 0.05 mm), and only this spherical portion of the
indicator to measure cup height. penetrator shall contact the specimen. The penetrator shall
5.2 Displacement Indicator—The displacement indicator move along the axial centerline of the top and bottom dies. It
shall monitor the ball penetrator movement and the scale shall shall be clean and free from oxide build-up, corrosion, dirt, etc.
E643–84 (1995)
5.3.2 The surface of the top die in contact with the test 7.2.1 The speed of the penetrator shall be between 0.2 and
specimen shall be plane and parallel to the surface of the 1.0 in./min (0.08 and 0.40 mm/s).
bottom die. Both surfaces shall be clean and free from oxide
7.2.2 Near the end of the test, the speed may be reduced to
build-up, corrosion, dirt, etc. the lower limit in order to more accurately determine the end
5.3.3 The surface finish of the penetrator and top die in point.
contact with the specimen shall not exceed 160 µin. (0.004
7.3 End Point of Test:
mm) when based on maximum distance peak-to-peak.
7.3.1 The preferred method for determining the end point
5.3.4 The spherical portion of the penetrator shall have a shall be by the drop-in load on the specimen. In general, this
hardnessnotlessthan62HRC.Theworkingsurfacesofthetop
indicates the onset of
...