How to avoid carbon contamination in graphite crucibles?

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Bapi Bera

Dear Miguel A. Callejas

I think it will be better if you use alumina/ceramic crucibles instead of graphite one and also alumina can go higher temperature than graphite.

Best Regards,

Bapi

Xuhua Wang

Further to Bapi's comments, an alumina coated basket has a low power rate and high melting point to do metal thermal evaporations easily. You could try it. It works very well in the past for us.

Zulfiqar Ali

Zirconia or yttria lining to graphite crucible is widely used technique to avoid the contamination of graphite particles into metal. please see further details regarding zirconia and Yttria coating on graphite crucible.

Regard