Material selection question for with molten Mg

Hello and thank you for reading.
I'm looking for advice or experiences in selecting crucible material for molten magnesium. The crucible should be metalic and the current candidate material is stainless 446.
This is a lowish carbon, 26% Cr and no Ni metal. I understand that Ni is avoided because it reacts with Mg. Is there a better alloy than 446? Would more chromium mean better service life? I fear the crucible will become too brittle at higher chromium levels but maybe there are alloying ways around that.
Any help or experiences are much appreciated.

snipped-for-privacy@hotmail.com wrote:
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Cr increases the chance of intergrainular corrosion. and Ni is important part of austenite stainless you should look ferretic Stain less steels for required properties .

On 29 Jul 2006 02:24:52 -0700, " snipped-for-privacy@googlemail.com"
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why not ceramic?

beav wrote:
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Ceramic is not historically used in this foundry. We are stick to what we know and probably cost is a factor as well.
Thanks for all the interest!

Due to the high reactivity of Mg melt, no metal crucible can be used to hold it. The ceramic crucibles are the only choice, but the impurities in commercial ceramic crucibles will be reduced and enter Mg melt, which leads to contamination. In my Ph.D. work, I prepared high purity MgO cricubles for holding Mg melts.
== snipped-for-privacy@hotmail.com wrote:
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snipped-for-privacy@prism.gatech.edu wrote:
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Could you give me a list of common impurities?