[wetterhorn]

Indeed, I've tried alumina, but any other powder materials should work. Creating a solid part is done by sintering or fixating (e.g. with resin)

[kephra]

what type of laser do you use for the SLS process?

[wetterhorn]

The SLS process hasn't been implemented for the Pwdr machine yet, but a small IR Laser has been used by others for SLS: http://builders.reprap.org/2010/02/first-tests-building-powd...