Max. retainment sleeve temperature for SmCo 2:17 2

[Clyde38]

What is the maximum temperature one can safely heat a rotor sleeve for installation over a permanent magnet rotor (of course without demagnetizing the rotor)? The rotor is magnetized SmCo 2:17. The sleeve would be something like 0.080" thick Inconel and the magnets are about an inch thick.

 

[MagMike]

Time at temperature is the biggest factor. A brief excursion to high temperatures for less than a minute will cause minimal degradation. If you can cool the SmCo and Inconel down quickly after sliding, you can probably heat the sleeve to 600degF.

 

[Clyde38]

Thanks Mike. We were going to heat to 275°C.

 

[EdStainless]

We used to even go a bit hotter. We used 700F.
Cooling after assembly is the key, and make sure that the rotor is cold to start with.
It does not need to be super cold, but normal freezer temp will help.
Why is you can so thick? For material with a 200ksi UTS 0.080" sounds like a lot of metal.
Good luck

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Plymouth Tube

 

[Clyde38]

Thanks Ed, that's good to know. You say cooling is the key, what extra steps did you use to cool the complete assembly? The rotor is for a 200 krpm device.