Magnetostrictive member and manufacturing method thereof

Abstract

The present invention provides a magnetostrictive member with high performance, high reliability and high versatility. The magnetostrictive member is used in the vibration power generation as a power source for extracting electric energy from various vibrations. The member made of the single crystal is manufactured cheaper than the conventional manufacturing method. The magnetostrictive member is formed by cutting a single crystal of Fe—Ga alloy by using electric discharge machining in a state that <100> orientation of the crystal of the Fe—Ga alloy is aligned in a direction in which magnetostriction of the magnetostrictive member is required.

1 . A magnetostrictive member formed by cutting a single crystal of Fe—Ga alloy by using electric discharge machining in a state that <100> orientation of the single crystal of the Fe—Ga alloy is aligned in a direction in which magnetostriction of the magnetostrictive member is required, wherein
 the single crystal of the Fe—Ga alloy is formed by separating a steel ingot into an individual single crystal at a crystal grain boundary of the steel ingot, 
 the steel ingot is formed of a plurality of coarse columnar crystals by using a unidirectional solidification method, 
 the <100> orientation of the coarse columnar crystals is aligned in a longitudinal direction of the steel ingot, and 
 a surface of the magnetostrictive member is shaped into a smooth surface by removing minute unevenness formed by the electric discharge machining using a polishing process without introducing strain on the magnetostrictive member. 
 
     
     
         2 . The magnetostrictive member according to  claim 1 , wherein
 a ratio of Ga in the Fe—Ga alloy is 19.0% to 23.0% by a mass ratio and the balance Fe and inevitable impurities.   
     
     
         3 . The magnetostrictive member according to  claim 1 , wherein
 an inclination between the direction in which magnetostriction of the magnetostrictive member is required and the <100> orientation of the crystal of the Fe—Ga alloy is 10.0° or less.   
     
     
         4 . The magnetostrictive member according to  claim 2 , wherein
 an inclination between the direction in which magnetostriction of the magnetostrictive member is required and the <100> orientation of the crystal of the Fe—Ga alloy is 10.0° or less.   
     
     
         5 - 6 . (canceled)