A Walk Through the Powdered Metal Sintering Cycle

In this video you can see the internal processes that take place when powdered metal material is sintered cleanly and efficiently.

[douglaslindsaychapman]

Is the copper part of the metal or as a slug that melts in.

[_cna]

does sintering always form porosity?
can we reduce the porosity formed?
does the formed porosity in sintering process has significant impact on mechanical properties?
thank you.