Heat Treating Inconel 718

[jimboux]

I have a couple of questions on the HT procedure for the 1700-1850 F Anneal and age that is in the Huntington Alloys book (attached).

As I understand the directions they say to
step 1) anneal at 1700-1850F
step 2) cool
step 3) aged at 1325F/8Hrs
step 4) cool to 1150F
step 5) age at 1150F total aging time of 18 hours
step 6) air cooled

Questions:
Cooling in step 2 can be slow in the furnace? I'm thinking we need to fully cool it then reheat to 1350, not just cool in furnace to 1350.

Cooling from 1350 to 1150 - after 8 hours can we simply change the furnace setting to 1150?

When does the clock start for the 10 hours of additional aging? When we set the furnace to 1150F or when the furnace reaches 1150F?

For the last air cool can we simply remove the parts from the oven and cool in still air?

 

[metengr]

I would suugest you use the reference below, it is more descriptive than your attachment, and provides specific guidance regarding HT;

http://www.specialmetals.com/documents/Inconel alloy 718.pdf

 

[jimboux]

Thanks metengr