Magnesium-Zirconium-Thorium alloys

[Paul_Hinrichsen/CNS1@cns.co.za]

I was recently asked to inspect the site of a local manufacturer of jet
engines and discovered, to my surprise, that certain engine parts are
manufactured from an alloy of magnesium-zirconium-thorium. The level of
thorium being as high as 325 Bq/g (concentration > 4%).

Does anybody out there have any information on this issue ?

In particular I am looking for answers to the following questions;

1.   How is the above controlled in your respective countries from the
point of view of the radiological hazards during   manufacture, handling
and final disposal ?

2.   Has anyone in the literature considered the radiological hazards
associated with the alloy ?

3.   Is this alloy only used in the manufacture of military jet engines or
does it have any other uses, particularly in       civilian aircraft ?

I would appreciate any input on the above issue.

Thanking you in advance. And compliments of the season to all you
Radsafers.

Paul

(phinrich@cns.co.za)


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