Hard Magnet : Effect Due Cutting Into Two Pieces

You need to run water or oil over the magnet during cutting to keep it cool.

Good advice from post #1. Good idea to re-magnetize the pieces after cutting. But permanent magnet materials tend to be very hard and difficult to cut. Impact may work better on brittle material. If you want many, buying them at right length is best. If you know what the material is, then information should be available on its long-term retention of magnetic strength and what causes loss. If magnets are cheap-enough for cover retention, chances are good it will be robust material - it is the expensive, high performance materials which are delicate.