Invar Ingot
Invar Ingot is used to craft 
Mixed Metal Ingot and for further processing. Tech Reborn doesn't have Invar ore.
Recipe
Crafting Table - Techreborn:invar Ingot
Alloy Smelter - Techreborn:invar Ingot
Usage
Invar Ingot could be used as a Beacon payment.
Invar Ingot is used in the following recipes:
Compressor - Techreborn:invar Plate
Grinder - Techreborn:invar Dust