MAGNETIC ALLOY HIGH IN INITIAL MAGNETIC PERMIABILITY AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce a magnetic alloy by a powder metallurgical method in which the shape, process and yield are satisfactory by forming a composition having a specified compsn. contg. Ni, Mn, Cu, and the balance Fe with inevitable impurities into a compacted body and sintering the body. ;SOLUTION: The composition has a compsn. contg., by weight, 60 to 71% Ni, 23 to 30% (Mn+Cu), and the balance Fe with inevitable impurities, and ≤96% (Ni+Mn+Cu) and 0.4 to 0.6 Mn/(Mn+Cu) are satisfied. The production is composed of a sintering stage in high temp. holding and a heat treating stage according to necessary. In the sintering stage, the compacted body is sintered at 1000 to 1350°C for obtaining an alloy having high sintered density. In the heat treating stage, it is heat-treated at a temp. lower than the sintering temp. by 20 to 200°C for securing the uniformity of the formation of the crystal grains and the compsn. of the magnetic alloy. Furthermore, it is preferable that the heat treating stage is obviated, and the cooling rate from the sintering temp. to a room temp. is regulated to 3 to 10°C/min.;COPYRIGHT: (C)1999,JPO