Alnico 5-7

[Zhangliqun]

What is this "Alnico 5-7" I see mentioned on charts but never offered as pu bar mags?

[LtKojak]

What is this "Alnico 5-7" I see mentioned on charts but never offered as pu bar mags?

I've had some samples from Magnetic Hold some years ago. It was a harsher, even more scooped than your normal A5. I didn't like one bit, but I'm not a fan of A5 either to start with, so... There you have it.

[Helmholtz]

What is this "Alnico 5-7" I see mentioned on charts but never offered as pu bar mags?

Alnico 5-7 is kind of premium A5. Its magnetic values (Br and Hc) are a few % higher than those of standard or average A5, while permeability is about 10% lower.

It has the same chemical composition as other A5s. So the difference must be in processing (heat treatment, magnetic orientation process).
It is already mentioned in magnet literature from the early 60s.