Coating for metal alloy

A metal alloy that includes an enhancement coating that is directly coated on an outer surface of said metal alloy;

• said metal alloy comprising rhenium and one or more additives selected from the group consisting of aluminum, bismuth, calcium, carbon, chromium, cobalt, copper, gold, hafnium, iridium, iron, lanthanum, magnesium, manganese, molybdenum, nickel, niobium, osmium, platinum, rhodium, ruthenium, silver, tantalum, technetium, titanium, tungsten, vanadium, yttrium, and/or zirconium;
• a combined weight percentage of rhenium and said one or more additives in said metal alloy is at least 98 wt. %;
• said enhancement coating has a coating thickness of 2 nanometers to 100 microns;
• said enhancement coating includes one or more layers of material coated on said outer surface of said metal alloy;
• said enhancement coating is at least partially applied to said outer surface of said metal alloy by a physical vapor deposition (PVD) process, a chemical vapor deposition (CVD) process, an atomic layer deposition (ALD) process, a plasma-enhanced chemical vapor deposition (PE-CVD) process, ion implantation, direct energy deposition (DED), and/or thermal spray technique;
• said enhancement coating has a composition that is different from said metal alloy;
• said enhancement coating includes no more than 0.1 wt. % nickel, and/or no more than 0.1 wt. % cobalt;
• said enhancement coating is formed of a) 35-95 wt. % zirconium and wherein said enhancement coating includes ZrN, ZrNC, ZrOC or a combination of ZrN and ZrO2, b) 20-85 wt. % titanium and one or more of carbon, nitrogen, oxygen, rhenium, and silicon, c) 40-85 wt. % chromium and one or more of carbon, nitrogen, oxygen, rhenium, and silicon, or d) at least 60 wt. % carbon.