This is a post by Cat McClintock on PTC site.
With additive manufacturing, you can create large, complex freeform parts from metal powder. But don’t skip the simulation step or your parts may cost more time and money than you ever planned.
One reason for that is the physical phenomenon of contraction. As the powder cools down, contraction can wreak havoc on your printed object, depending on the actual geometry and its continuums mechanics.
In this article we discuss three common unwanted outcomes in metal 3D printing caused by contraction, all of which can be easily avoided by running simulation well before you start physical manufacturing.