Inconel Flange for High Temperature Furnace

Q: I was wondering if it would be okay to use the Tantalum material in a furnace with design temperature of 2600F. It is a heat treating furnace and I need a 4″ 150 ANSI RF flange.

A: Generally due to its extremely high price, tantalum is produced as weld overlay on steel for corrosive applications. Making a solid tantalum flange is not practical and not a good choice for high temperature applications. If your application is in a vacuum or inert atmosphere as at those temperatures of 2600F you may consider a material like molybdenum. If the flange is exposed to oxygen, an Inconel flange would be about the best you could get.