US Patent 7479193 Preparation of positive magnetostrictive materials for use under tension

A positive magnetostrictive material such as a ferromagnetic alloy is subjected to a magnetic field during annealing treatment while being heated for a predetermined period of time at an elevated temperature below its softening temperature followed by cooling resulting in a treated ferromagnetic material having high tensile strength and positive magnetostriction properties for enhancing use thereof under tensile loading conditions. Such treatment of the ferromagnetic alloy may be augmented by application thereto of a compressive stress.