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Is tin a problem in galvanized coatings?

Has anyone heard of the recent use of increased tin content in zinc galvanizing baths causing problems with liquid-metal-embrittlement (cracking) of galvanized steel? I have heard this from one source, but haven't been able to confirm it. I work for a commercial insurance company and would like to know if this may be a growing problem.

Thanks,

Mark Gilkey
galvanizing - Norwood, Massachusetts
2004

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The addition of Sn to galvanizing baths was raised at Intergalva 2003, the international Galvanizers conference. Several papers touched on this topic. Sn is being added to increase fluidity near melting (freezing) point to assist in cleaner galvanizing (fewer spikes). In addition, fluxes containing Sn have been developed as alternatives to the more traditional ammonium chloride . Zn chloride. I don't remember any mention of this leading to increased embrittlement or LMcracking.

Sn in steel however, in combination with Cu can lead to hot shortness cracking, but thats a steelmaking issue rather than a galvanizing one.

Geoff Crowley
Crithwood Ltd.
Westfield, Scotland, UK

2004