A FEA model, representing a structure, contains at least many finite elements for
metal portion, a set of
metal necking failure criteria (critical and fracture strain values defined in form of a loading
path diagram) and the neck's characteristics (neck's width and a profile of strain values within the width) are received in a computer
system. At each solution cycle of a time-marching
simulation using the FEA model, following operations are performed at each
integration point of every finite element: identifying
major and minor strain values and corresponding directions from the computed strain values, calculating an equivalent
metal necking failure strain value (εe) in the major strain direction with a formula based on corresponding critical and fracture strain values, the neck's characteristics and a characteristic dimension with respect to the major strain direction, and determining metal
necking failure, which occurs when the major strain value is greater than εe.