Do I need a special Metglas core?
No. Good results can be obtained with standard materials such as silicon iron. It is also far more important to understand the force point for the apparatus you are using, and match the magnet strength to the flux saturation point / depth of the core. Intelligently used silicon iron will deliver much better results than aimlessly pulsing Metglas. In an ideal world, you’d model your apparatus in flux software, so you can get the maths / input levels spot on.
