Contrary to what you would think, name Ferroelectric RAM often misleads people to the misunderstanding that FRAM are strongly affected by external magnetic field.
Nevertheless, Ferroelectricity does not contain ferromagnetic materials and has nothing to do with magnetism. While memory devices using ferromagnetic or antiferromagnetic elements, such as Fe, Co, Ni, Cr, etc., their related materials and/or compounds, are strongly affected by external magnetic field, Ferroelectric RAM devices are basically not affected by magnetic field because they do not use ferromagnetic or antiferromagnetic elements.
Fujitsu "FRAM FAQ"
Cypress Semiconductor Corp. "F-RAM(TM), nvSRAM, and MRAM Magnetic Field Immunity"