scope:

Scope of Test

Assess localized fracture properties on parts (e.g. joining flanges/embossments) or material test coupons. Generally, for aluminum sheet and extrusion materials, the 3 Point Bend Test (FLTM BB 119-01) should be prioritized. If material fracture cannot be achieved within the 3 Point Bend test, then this pierce test or other material fracture characterization methods should be used.

The punch test is dependent on thickness and strength of the material. Therefore, comparison of test results is most accurate when tests are performed on material of comparable thickness and strength levels. The distance to fracture (break displacement) is the preferred metric for SPR button formability.