Plasma Immersion Ion Processing for Coating of Hollow Substrates: 8,029,875

The present disclosure relates to a method for plasma ion deposition and coating formation. A vacuum chamber may be supplied, wherein the vacuum chamber is formed by a hollow substrate having a length, diameter and interior surface. A plasma may be formed within the chamber while applying a negative bias to the hollow substrate to draw ions from the plasma to the interior surface of the hollow substrate to deposit ions onto the interior surface and forming a coating. The coating may have a Vickers Hardness Number (Hv) of at least 500.