There is a printing-powder and a metal-powder tag.
The respective use of each tag, to date, is as follows:
One of the printing-powder tagged questions is closed, and the other is also tagged metal-powder, and both questions were about metal-powder.
Therefore, should the two tags be merged, as (currently), they both refer to the same thing, namely, metal powder?
I guess that, as there is other printing powders available, the printing-powder tag could be left in-situ, but why not remove it, and if it is subsequently required, then let it be recreated?
[and/or]... remove the double tagging from this question, Why can't powder-based 3D printing techniques create enclosed or hollow structures?