In another question, I had a little comment-discussion with TFD on the effect of shock cooling on pans. In a nutshell, I said that it is bad for the pan, and he said that especially if the pan is made of steel, it should have been at 500°C for the shocks to have consequences, not at candy cooking temperature. I think that if it happens often, even at low temperatures, the internal structure of the pan would be less even (because of microcracks, or maybe some difference in the crystalline structure of the metal), leading to hot spots.
I'd like to broaden the question a bit. I think we will all agree that big temperature shocks have bad consequences on metals (think forging). I think that smaller shocks will have some (but smaller consequences), but after TFD's comments I am not sure. Could please somebody with better knowledge about metals explain what happens in different combinations of following combinations:
- Cooling method
- Immersion of the whole pan in cold water (as in, I have hot sugar syrup in it, and want to stop the heating immediately).
- Pouring a small amount of cold liquid into the empty hot pan (as in deglazing).
- Pan material
- Stainless steel
- Sandwiched bottom
- Coated (e. g. enamel, PTFE, ceramic)
- Temperature difference (our cold water is in all cases in the range 5°C (fridge) - 15°C (tap))
- Steak/candy temperature (let's pick a range of 160°C - 200°C because of caramelisation and Leidenfrost)
- Hottest stove temperature (because I want to know about the extreme case. 400°C or 500° should do, the first because that's what I am sure have had on my stove, the second because TFD mentioned it).
Let's assume not a single shock, but regular shocks (maybe two shocks a week over the lifetime of the pan). What will be the effects? And also, is there a combination which can (but will not always result in) crack a cast iron pan immediately?