Metal components with inert vapor phase coating on internal surfaces

A metallic component having a lumen, passageway, or cavity having an interior surface continuously covered with a protective coating having a substantially uniform thickness of about 10 nm to about 5 μm wherein the protective coating is formed via a vapor phase process comprising:

• providing one or more molecular precursors in the gas phase;
• exposing an interior surface of the lumen, passageway or cavity to the one or more molecular precursors in the gas phase;
• allowing the one or more molecular precursors to react, decompose or otherwise change at or near the exposed interior surface and subsequently depositing thereon;
• and flushing with an inert gas, thus removing unreacted one or more molecular precursors and reaction byproducts, if any;
• wherein the metallic component is a chromatographic column comprising an inner diameter of less than 10 mm and a length greater than about 20 mm;
• wherein the protective coating comprises a material selected from SiC, Si3N4, SiOxCy (wherein 2x=4y=4), SiOmNn, (wherein 2m+3n=4), SiCxHy (wherein 4x+y=4), TiO2, ZrO2, Al2O3 or a mixture thereof.