On factors affecting localization and void growth in ductile metals: A parametric study

A large number of factors besides void volume fraction are known to play si gnificant roles in influencing void growth and strain localization. In spit e of this, macroscale constitutive models currently available in the litera ture account for only a few of these factors while describing the evolution for damage, or porosity, in ductile metals. The absence of other contribut ing factors from the models could be attributed to the fact that past inves tigations have considered only a few (at most three) while determining thei r overall influences on void growth and strain localization. The present st udy seeks to examine the sensitivities exerted by a list of seven independe nt parameters on strain localization and void growth in Aluminum 1100 and 3 04 L Stainless Steel by performing a series of parametric calculations usin g the finite element method. Owing to the wide range of parameters, an opti mal matrix of finite element calculations is generated using the statistica l method of design of experiments (DOE). The DOE method is also used to scr een the finite element results and yield the desired parametric influences as outputs. As far as localization and void growth are concerned, it is obs erved that, while temperature and microporosity exerted the most dominant i nfluences, pre-strain effects and geometric parameters, such as uniformity as pore size, and the shape and distribution of pores, are noted to play si gnificant secondary influences.