SINTERED MOVABLE IRON-CORE AND METHOD OF MANUFACTURING THE SAME

A sintered plunger is used for electromagnetic actuators. The sintered member includes: an outer member composed of a soft magnetic material and having an inner hole formed therein, and a shaft having an end portion which is fitted into the outer member. The shaft is composed of a ferromagnetic steel, the outer member peripheral is composed of a sintered member, and the shaft and the outer member are integrally bonded by sintering. As a result, the overall sintered plunger can have good magnetic properties, a good magnetic attraction, a good wear resistance, and a good fatigue strength. Electromagnetic actuators having high responsiveness required in recent years can be produced.