Nice idea Tuc. The inner fins look like they would pull a significant amount of heat out.
Nickel is a interesting alloying material. Commonly used in some high end auto brake rotors mostly to keep them clean looking and preventing them from rusting badly. E. Plated mostly. Alloyed in, in my experience a little goes a long way. Adds to corrosion resistance, but is somewhat soft, and slippery. It is known for adding to heat resistance of steel but also suffers from loss of heat dissipation. Looks to be a good alloying element in making cook ware rather than brake rotors. Tungsten would be my guess as a adder of choice in steel rotor apps subject to red hot operation.
For bikes or ebike, it looks like a more common A2 may be a good starting point. Lower in chrome and no nickle going by a few published data sheets.
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C-dale Jekyll Bad boy ultra http://endless-sphere.com/forums/viewto ... =6&t=51830