Annealing

You are changing the crystal structure when you anneal, you have to get the material hot enough to do that, doesn't matter how long it sits at a lower temperature if it doesn't get past the critical point. A kitchen oven can do some tempering, but can't get hot enough to do annealing. Also, some types of steel, like the air-hardening types, need a specific regimen of heating and cooling to anneal them, you'd need a programmable heat treat oven to do that. Not all steel is the same, you know!

Looks like you need some education on steel and heat treatment. You might get some books at the local library, there's also a bunch of old ones for free at this site:

Use "heat treatment" for searching.

Stan

^^^^^^^^^^^^^^^^^^^ It's hot enough to "draw the temper," a step which reduces the brittleness and increases the toughness, after quenching. It is not hot enough to anneal the steel, no matter how long you leave it.

Not to be critical, but you can't "soften" steel in a steel oven. It has to have serious insulation, so the steel holding the oven together doesn't get soft, too.

Anyway, you need to get at least red hot to anneal steal, somewhere in the 1700 F range. Not even a self-cleaning oven gets that hot.

Jon

How big a piece?

Small enough, and you could stick it directly on the burner, to heat it red or near to. In any case, expect lots of oxidizing to occur. Big scabby flakes of it, as you are unlikely to be able to keep the oxygen off it.

Cheers Trevor Jones

Yes, I know that.

It's the temperature of an oven I was checking on - if perhaps a v-e-r-y long soak would work.

Hmm, underscore, are you perhaps related to dear old asterisk?

No. You can temper plain carbon steel in a domestic oven, but you simply cannot anneal it. Even on the cleaning cycle you don't get past 700F, typically; 800-1000 degrees F less than you need. The science of heat treating is rather well documented if you'll just bother to look - not only temperatures, but the physical chemistry underlying the temperatures, rates of cooling, etc... Books from a library tend to be the best bet, but there's a good deal of general info on the web, too.

Not that it makes any difference to the topic at hand, but just an FYI, I stuck a thermocouple in our GE just now during a cleaning cycle. The temp ranged from a low of 790F to a high of 832F. I don't know if that's typical or not.

Wrong order though. Coffee, cats, chocolate. ;-)