ASTM E643-84(2000)

The ball punch deformation test is widely used to evaluate and compare the formability of metallic sheet materials. Biaxial stretching is the predominant mode of deformation occurring during the test and, therefore, the results are most often used to rate or compare materials that are to be formed mainly by stretching. However, precise correlations between the cup height as determined by this test and the formability of a sheet material under production conditions have not been established.

It is recognized that the cup heights for specimens from the same sample may vary with differences in magnitude of hold-down force, lubrication, and method of end point determination. The procedures described in Sections 5, 7.1, and 7.3 will minimize these variations.

1.1 This test method covers the procedure for conducting the ball punch deformation test for metallic sheet materials intended for forming applications. The test applies to specimens with thicknesses between 0.008 and 0.080 in. (0.20 and 2.00 mm).

1.2 The values stated in inch-pound units are to be regarded as the standard.

Note 2--The modified Erichsen test has been standardized in Europe. The main differences between the ball punch deformation test and the Erichsen test are the diameters of the penetrator and the dies. Erichsen cup heights are given in SI units.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.