Replies

Magnetic susceptibility of hard-drives is low to increase reliability & data integrity.

Magnetic susceptibility is the degree of magnetization of a material in response to a magnetic field.

You need a device capable of high coercivity to overcome magnetic susceptibility.

Coercivity is the intensity of the magnetic field needed to reduce the magnetization of a ferromagnetic material to zero after it has reached saturation.

You could take a motor coil and place the hard-drive inside of it and then apply a large current to the field windings, that would more than likely erase the contents of the drive. This offers a high coercivity since an intense magnetic field is created that can overcome the susceptibility.

I deal with this in a similar area, power transformers and power transformer protection.

MD