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Max operating temperature of aluminum

I have an application for a aluminum heating block for industrial purposes. The temperature of the block must reach 1000 degree F max. I am aware that the melting point of aluminum is 1200 degree F. Can I still heat this block of aluminum to 1000 F even though its close to the melting point?

William Freshour
instrument co. - Bohemia, NY,USA
2005

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First of two simultaneous responses --

No. It will lose 80-90% of its mechanical properties and behave like putty.

Guillermo Marrufo
Monterrey, NL, Mexico
2005

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Second of two simultaneous responses --

Good afternoon:
Is the heating block pure aluminum or an alloy? Aluminum alloys will partially melt well below the melting point of pure aluminum. If you have access to ASM Metals Handbook Vol. 2 'Properties and Selection: Nonferrous Alloys and Special-Purpose Materials' [on on Amazonaffil links], there should be plenty of information to help you with this application.

Steve Bizub
- St. Louis, Missouri
2005

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William, you may want to rethink your plans. 2024 is a pretty common aluminum alloy. It starts to melt at 935 F. 7075 is another common high strength alloy, and it will start to melt somewhere between 890 and 990 F, depending on the amount of working the cast billet received.

As Guillermo pointed out, the mechanical properties will be greatly reduced- and they'll drop even more if part of your block melts. If you're stuck with aluminum, make sure you're using something like 6061 (1080 F) or 3003 (1190 F).

Lee Gearhart
metallurgist - E. Aurora, New York
2005

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Q. Looking at other alloys, 6061 and 7075 specifically, what level of mechanical properties degradation would be experienced with only a 250 °C soak for 4 hours?

David Woodruff
- San Jose, California, USA
November 1, 2012