Inconel 600 Bolts vs. Inconel 601 Bolts

Q: Can you tell me what the difference is between Inconel 600 and 601? I need a material for high temperature thermal cycling.
A: Both Inconel 600 and Inconel 601 bolts are oxidation resistant at  high temperatures. The main difference is that Inconel 600 bolts have a maximum usable temperature of 2000°F, where Inconel 601 screws can be used at higher temperatures up to 2200°F. In addition, Inconel 601 bolts perform well in cyclic temperature conditions.
Another material to consider for cyclic conditions would be Alloy 330 which is very oxidation and carburization resistant to 2100°F. Plus,  Alloy 330 bolts are known for the ability to perform in cyclic conditions of temperature extremes.