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Anodized aluminum or titanium for high temperature

Q. I am working on the design of a fixtures that hold samples inside a thermal chamber.

My problem is that this fixture must be very light and resist to temperature up to 400 °C. At room temperature, we use aluminum but over 150 °C, I doubt that without anodizing or any other finish, fixtures will work! But is anodizing sufficient or will it crack by expansion of the parts?

And is Titanium is the only light material that can support high temperature? Is there any other finish to apply to aluminum to permit parts to resist up to 400 °C?

Thanks!

Frederic Wallman
- Montreal, Quebec, Canada
February 15, 2012

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February 22, 2012

In 400 °C temperature aluminum will oxidize, but very slowly. Probably such situation will be OK for you. As to cracks - they will "heal" by themselves in high temperature by forming new aluminum oxides. Also aluminum anodized layer of only 20 mkm will be sufficient enough.

Titanium is oxidised very fast in comparison to aluminum. Titanium will also consume oxygen. We do not recommend it.

Anna Berkovich
Russamer Lab

Pittsburgh, Pennsylvania

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February 24, 2012

Thank you for the answer!

But considering anodized aluminum, my doubt is that, as my fixture is assembled with screws, they deform the part at high temperature and stay stuck inside! Is it possible?

In fact, can an assembly with screws be unscrewed when it bears temperature up to 400 C?

Frederic Wallman
- Montreal, Quebec, Canada