Failure Criteria for a sheet metal

[jonster87]

Hi guys,

I require the constants for the Johnson-Cook plastic and damage models, but only have access to the values for the Hill criterion (1948),
Is there anyway to use the hill criterion to obtain the values for Johnson cook?

Cheers in advance

 

[CoryPad]

Johnson-Cook has been discussed at Eng-Tips a few times, do a site search and see if those previous threads help. You can try a nearby university library and review journal articles that cover this area.