Good evening all,
Within my work, I predominantly use Simulation Mechanical for linear static analysis on below-yield multi-body assemblies. However, just out of interest today, I decided to run a non-linear, static stress simulation on a material test specimen model.
I am using a von mises, isotropic hardening material model, with plasticity output enabled.
Ramping the load up to max at half the total time steps, back to 0 - the specimen passes yield, and indeed passes the ultimate tensile strength - with no necking occurring, but rather the entire test specimen length narrowing uniformly.
I thought perhaps the lack of real world material imperfections was the issue, so I modelled a small central spherical inclusion to try to induce a stress riser. Still no necking, but a local higher stress of course.
I have also attempted the same with a variety of materials, varying in ductility.
Any ideas as to perhaps what needs to be done to predict necking? ...again - this is purely out of interest.
Many thanks in advance.
