Vacuum impregnation  seals porosity and leak paths in metal castings and powdered metal parts that form during the casting or molding process. The process is done by filling the pores with a sealant under pressure to stop fluids or gases from leaking under pressure. Vacuum impregnation stops casting porosity and allows manufacturers to use parts that would otherwise be scrapped.

 

This video shows the 4 steps on how vacuum impregnation seals porosity.