Normalized lead alloy

[joeb33050]

A man has written and asked me what "normalized" means, in reference to lead alloys; and how it is done.
I looked up the word, and got
"To remove strains and reduce coarse crystalline structures in (metal), especially by heating and cooling."

I THINK that normalizing lead alloy pieces is done by heating them up to ?? temp., and slowly cooling them down.

Sort of like annealing iron alloys.

Does anyone know?
joe b.

[JSnover]

It's stress-relieving. Sounds odd to worry about that with lead but there are plenty of folks oven-treating their boolits to soften them or reduce brittleness. You are correct about the procedure. Get them into the transformation temp and let them cool slowly.

[montana_charlie]

The man may have asked for exactly the information he wanted, or he may have meant 'stabilized'. Dan Theodore did a 28-week test to determine how much hardness change exists in a group of common casting alloys, and how stable those changes are.

Pretty much all of his (various) results were surprising to me...

CM

[leftiye]

I only use the abnormal stuff, It's harder.

[Ricochet]

Only use that if you want normal boolits.

[runfiverun]

you can change grain structure in an alloy by adding other elements to it like arsenic or sulphur.
they can tighten the grain structure.
you could also take a heat treated or watertreated boolit alloy and return it to normal hardness by re-melting it or waiting the interminable time period for it to happen.

[BABore]

you can change grain structure in an alloy by adding other elements to it like arsenic or sulphur.
they can tighten the grain structure.
you could also take a heat treated or watertreated boolit alloy and return it to normal hardness by re-melting it or waiting the interminable time period for it to happen.

Or you can put hem in a 400F oven for an hour and shut it off. Remove the boolits in the morning and they will be dead soft. WW's will actually anneal to below their normal air cooled (10-13 bhn) state for about 12 hours afterwards. Then they will return to their normal AC state.

Through oven annealing and proper temperature control, you can draw back OHTWW's that are 28 bhn, incrementally. I did a lenghty test a few years back and took the WW boolits from 28 to 14 bhn in 2 bhn increments. Each step up in temperature would drop the bhn. IIRC I started at 225 F or so and worked the annealing temperatures up in 20-25 degree increments. The chart I have squirreled away somewhere only worked for straight WW's. I had to adjust the temperature when working with my normal 50/50 WW-Pb alloy. This experiment was extremely useful for finding the exact bhn that performs best in some guns.

[joeb33050]

Where can I read Dan's report?
Thanks;
joe b.





The man may have asked for exactly the information he wanted, or he may have meant 'stabilized'. Dan Theodore did a 28-week test to determine how much hardness change exists in a group of common casting alloys, and how stable those changes are.

Pretty much all of his (various) results were surprising to me...

CM

[montana_charlie]

Where can I read Dan's report?
Thanks;
joe b.
Uhh...it's on that forum where you like to dump your garbage.

CM