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View Full Version : Calcium? = hard lead?


sav300
06-26-2009, 06:37 AM
Just been handed a jar of calcium and told it hardens lead. A light sprinkle on the melt.

Anybody have any info or suggestions?:roll:
waksupi
06-26-2009, 08:52 AM
I suggest it will not harden lead.
GLL
06-26-2009, 10:33 AM
Nope !

I doubt what you were given is calcium since it is VERY reactive in elemental form !

Even in the form of one of the many calcium salts or oxide it will not harden Pb.

Jerry
snaggdit
06-26-2009, 06:17 PM
Yeah, calcium is similar to sodium and lithium (in the same column on the periodical chart IIRC from college). In a pure state it will react with water alone. Not as violently as lithium which will flame and dance on the surface of water but it will boil and release heat.
stubshaft
06-26-2009, 10:53 PM
I would think that it easier to use 1 - 2oz of lead shot per 20lb pot of lead to harden it. About 2 - 12ga shot gun shells worth...
BOOM BOOM
06-27-2009, 12:30 AM
HI,
I would not use it.
Ca is a very reactive metal in the pure state it will react w/ the O2 in the air to form an white oxide crust on the surface or the metal .
It might be dangerous to even drop a fingernail sized piece into molten Pb.
uncle joe
06-27-2009, 12:41 AM
it will however harden concrete :mrgreen:
Bret4207
06-27-2009, 08:03 AM
Yeah, calcium is similar to sodium and lithium (in the same column on the periodical chart IIRC from college). In a pure state it will react with water alone. Not as violently as lithium which will flame and dance on the surface of water but it will boil and release heat.

The 12 year old boy in me suddenly desires a good quantity of lithium and a swampy pond on a foggy night! Now THAT'S entertainment!:mrgreen:
longbow
06-27-2009, 10:35 AM
Calcium lead alloys are used for lead acid battery grids and I thought the calcium was to replace some of the antimony to get better corrosion resistance and to harden. From what I see on the internet it it is used for several reasons, corrosion resistance being one but no mention of hardening.

In any case, I do not know what form of calcium is added to the lead or under what conditions and I doubt it would be easy to add at home since calcium is very reactive.

I will ask the metallurgist at work on Monday.

Here is a good link on lead alloys:

http://www.lasc.us/CastBulletAlloy.htm

And another good one:

http://nonferrous.keytometals.com/default.aspx?ID=CheckArticle&NM=88

No direct mention of hardening effect just that it is used to replace some or all antimony.

Longbow