CowboyME1
Mechanical
- Feb 27, 2019
- 1
Ok, so I got asked a question that I cannot answer definitively with the AMS Heat Treating book, nor AMS 2770. Our heat treating shop has a batch of 7075 sheet in the aging furnace. They are taking it to T6. We are having a winter weather event here and they are concerned that the next shift won't be able to make it in. By then, the heat will be half way through the ageing period (12 of 24 hrs) We have a rule that the furnace cannot run unattended, so they may have to abort the ageing process midway through. They want to know whether they can pick it up tomorrow and run it the rest of the way out. My intuition is telling me that won't work. but AMS only addresses interruptions obliquely. The iso-yeild-srength curve shows that we won't have reached T6 by then, and there is verbiage about failing to remain in nominal temps will greatly effect strength. So killing the juice will clearly cause us to deviate from nominal. However, there is no guidance as to what to do afterwards. My inclination is to have them start over from scratch, but I'd really like to know if there is a specific alternative.