Heat Treating 1045

[FERRARIVS]

Hi guys,

I've done all the searches I can think of and haven't found any direct instructions on easily heat treating 1045 steel without being able to directly measure high temperatures, so can anyone offer any advice on doing it properly sans thermocouple/pyrometer?

I've made a hammer and followed the only basic hardening/tempering instructions I did find, which simply said to heat to a nice cherry red, quench 1" or so of the face end, polish quickly and wait for the blue color to develop, then quench fully. Well that didn't work worth a xxxx LOL The specific directions I found call for heating to 1500F then allowing slow cooling, reheating to 1500F then quenching, and lastly heating to 600-1200F (weirdly broad?) with a final slow cooling. Of course I understand what the steps are, but just don't have the means to measure such high temperatures... help!

Thanks

Matt

[rthibeau]

for a hammer....heat the whole thing until it is nonmagnetic, then quench the whole thing in water....clean it up with a sander so it is shiny, then heat inside and out around the eye with a torch until the colors start to run.....when both ends are barely turning purple on the edges, fully quench. Clean up and sand it, then put a handle in it.

[ThomasPowers]

1: are you sure it's 1045?
2: What were you quenching in?
3: What was the problem you saw---too hard or too soft or self destruction/cracking?

The devil is in the details!

[FERRARIVS]

Yup, it's 1045 for sure- I bought it from a steel supplier, it's not scrounged material. I quenched it in plain water, not brine or anything and the problem is that it's a bit soft- the edges are rounding (it's a square-faced hammer).

Barely purple at the edges is earlier than I stopped the tempering- I waited until the face was fully blue, so certainly softer...

[ThomasPowers]

Did you quench in a lot of water moving it constantly or with a hose directed on the face to get through the steam layer? Or just in a coffee can?

(also steel suppliers have made mistakes before; but they have a much better record than scrap steel does!)

[FERRARIVS]

Oh sure, but in this case I saw the stock bar they cut my piece from and it was labelled 1045. I use a large probably 20L bucket full of water and yes, I kept it moving. The face was only just warm when I polished it with emery cloth. But then I did let it go completely blue before I quenched it again (a deep plunge again moving).

It was a second attempt though- the first time I quenched more of the length and I wasn't seeing any color change for what seemed like too long a time, so I heated it to cherry again, etc. I didn't normalize it either after forging or between heat treating attempts- perhaps I should have?

[dablacksmith]

another thing to remember is the number of times it was heated ...... if you heated it a number of times you can have carbon loss ... usually shows up if it took a lot of heats to punch and forge ...good luck!

[ThomasPowers]

So, you never had help mislabel stuff? (You're right that it does lower the chance but it doesn't make it 0! I remember how shocked my kids were when I would correct things in their school books and going head to head with their teachers when they held to an obvious mistake "cause the book said so!")

If it is decarb you may be able to file off the soft layer and find a harder layer lurking below it.

[rthibeau]

Ferrarivs...I'd have to repeat my earlier posting. The steps are heat to nonmagnetic, quench fully, heat around the eye until the colors run, then fully quench again when the edges just start to turn purple.......fully blue is too soft for a hammer face

[Frosty]

Originally Posted by rthibeau

Ferrarivs...I'd have to repeat my earlier posting. The steps are heat to nonmagnetic, quench fully, heat around the eye until the colors run, then fully quench again when the edges just start to turn purple.......fully blue is too soft for a hammer face

I agree fully; you just drew the temper a little too far. This hammer is from a Ford pickup axle. It's a bit darker than it appears, in the pic. light purple, and is a bit soft but that's okay, it can't damage my anvils.

Frosty