we need binding material to produce uniform compaction and that binding materials will not produce gas.
Practically all binders in powder metallurgy are organic compounds and form gas during sintering (binder evaporate). That's the point of the matter: a binder has to be removed from pressed bodies and evaporation is the best way to do it.
In theory, you can use a fusible soft metal binder for compacting, such as lead or tin. Such binders will not evaporate during sintering but will melt and drip, however that would not be a good idea: part of the binder remains in sintered body and oven is messed up with melt.
If you need to compact FCC metals powders, you can apply a binderless cold sintering process (at a pressure of 2-3 GPa). No any gas will be released in this case through a following "hot" sintering. You need just to use a properly constructed rigid die to apply a uniform compaction. Then you need to perform reduction gas assisted cleaning of the green body, and only then - "hot" sintering. I sucessfully performed such processing many times even on non-FCC metals and metal-ceramic powder blends.
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