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High temperature of SS alloys

We have a high temp process (~1000degC)involving heating of a product containing Li in high temp alloy pots (Haynes 214) We are getting a deliquescent film of Lithium Chromate forming at the end of the process. Can anybody suggest a suitable passivation process?

Simon Jolley
- Auckland, New Zealand
2003

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Haynes 214 is a Ni75-Cr16-Al4.5-Fe3 (Mn < 0.5) alloy. Passivation will not help; lithium oxide is considerably more thermodynamically stable than chromia on an equivalent oxygen basis. An argon atmosphere low in oxygen (< 100 ppm) should be used. For container material, refractory metals (niobium, tantalum) are recommended. Of the stainless steels, ferritic or martensitic grades high in Cr and low in Ni, Mn and C are preferred. -- ASM Metals Handbook Vol. 13 'CORROSION' [affil link on Amazon]

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2003