This part of GB/T 15825 specifies the laboratory measurement method for forming limit diagrams (FLD) of sheet metal. This section applies to thin metal plates with a thickness of 0.20mm~3.00mm.
GB/T 15825.8-2008 Referenced Document
GB/T 15825.2-2008 Sheet metal formability and test methods.Part 2:General test rules
ISO 12004:1997 Metallic materials - Guidelines for the determination of forming-limit diagrams