Unknown steel, normalize or anneal before forging?

[caotropheus]

Greetings

 

I have access to agricultural machinery and scrap steel I can extract from there (flail shredder hammers, mechanical hoe and soil tiller blades, plough shares, springs, harrow disks and such) . Usually, before I use this steel, I normalize it a couple of times. But, during the Winter it is much easier for me to anneal this steel. I Just toss the steel inside the wood stove by the evening, the next morning the steel is annealed. So my question is, what is "better" (obtain a less brittle steel)  to reuse scrap steel, anneal it or normalize it before forge my tools? Thanks

[Daswulf]

You dont need to do either before forging it. Maybe for stock removal or machining but if you are going to actually forge it you don't need to do anything but heat to proper temps for the steel and beat it to shape. After being any heat treat you need if drilling or working cold. But forging you need no pre treatment. 

The only thing you need to worry about or treat is if it's galvanized or chrome plated. Then precautions or treatment or "dont bother" is necessary. 

[ThomasPowers]

Normalizing is used in knifemaking for some alloys to refine the grain; but that's just before the hardening step.  Unless the steel you are using has gosh awful large grain to start with I don't see how normalization before forging would do it any good.   Annealing is usually done before machining, (milling, drilling, grinding, filing, etc), to make the steel softer when it is cold.  It's already soft when it's hot; so again another unneeded step.

With scrap of those types you may run into alloys that are not much fun to forge and may be impossible to heat treat with blacksmith methods, in particular the high speed steels, high alloy steels and the boron alloys used for shredders and high impact cutters.  Learning to spark test those to give you a hint at which should remain in the scrap pile would be more of a help in forging than doing un-needed heat treats.