I just got back from a workshop in Adelaide where I gave a presentation on this technology and may be able to clear up a few misconceptions about the process. When I first heard about "laser sintering" I was as put off as most engineers are since the perception is a course, porous structure that lacks strength and ductility.
The reason that this was initially called laser sintering is because the first lasers didn't have the power to fully fuse the powder so it was a 3d printed structure that most closely emulated sintering without a mold. Now laser power is 400 plus watts and the material is fully fused with properties that are as good as billet. Here is a slide showing the difference in grain structure between sintered and SLM:
If the part is fully dense, then why does it still appear sintered? For the same reasons that low powered lasers caused incomplete fusion in the beginning. The section of the model where the laser travels will be fully fused through several layers. However, just outside the actual model section is an area where there is still a lot of heat and the adjacent powder will partially melt and adhere to the fully fused section. This is the area of surface roughness that is visible unless cleaned up. So if the wall section is 1.5mm thick, the actual thickness may be 1.55 - 1.65 thick until cleaned up due to the particles that are clinging onto the actual fused model structure.
This is actually an advantage in suppressors. By having the rough texture inside and out, you end up with far more surface area which is beneficial for heat exchange purposes. Because the sections are thin and light they do heat up very fast and cool down very fast.
I have cans that are used for limited FA and semi auto applications. For extended FA I can make Inconel 718 using the same techniques to reduce weight.
