Scope:

The deformation of a ball punch is a regularly used test to assess and evaluate the formability of metallic sheet materials. The most common mode of deformation is biaxial stretching. Stretching is the primary method of formation in these tests.

Procedure

As a lubricant, commercially available petroleum jelly is used only. The specific surface is not altered, which is representative of the material as a whole, mechanically or chemically. Only the punch is lubricated and a small layer of lubrication is applied to it. Other lubrication and specimen preparation systems are insufficient. The specimens and lubrication are used in accordance with the terms agreed upon by the supplier and the user. The penetrator’s speed should be between 0.2 and 1.0 inches per minute  The procedure for determining the endpoint with the results of the tests is determined. At the start of the test, the penetrator displacement indication is set to zero. When the penetrator makes contact with the specimen under test conditions, the test begins.

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Specimen size

Specimen blanks should be either circular or rectangular with a diameter or width of 3.5 in or 90 mm.

Result

The test result is a ball punch (penetrator) movement to decrease in-load or necking or fracture.