PURPOSE: To manufacture an inexpensive nonmagnetic steel sheet of high quality by rolling a high Mn nonmagnetic steel slab, at a specified temp., obtd. by steel refining with a converter, reduction refining with an AOD furnace, continuous casting, cover cooling and working.
CONSTITUTION: The chemical composition of a high Mn nonmagnetic steel is adjusted to about 0.20W0.80% C, ≤ about 0.50% Si, about 17.0W30.0% Mn, ≤ about 0.030% P, ≤ about 0.030% S, about 1.0W9.5% Cr, ≤ about 0.030% sol. Al and the balance Fe. This steel is refined with a converter, subjected to reduction refining with an AOD furnace, and continuously cast to ensure homogeneity for the material. The cast slab is then slowly coole under a cover, worked with a grinder, heated to about 1,200°C at about 100°C/hr heating rate, and rolled to a predetermined thickness at ≥870°C. Thus, the desired sheel steet can be otd. without carrying out soln. heat treatment.
IWASE KEIGO
KISHIDA TATSU
NAKAMURA TAKESHI
ANDOU TERUHIRO
ODA KAZUHIKO
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