Texture formation and aging behavior in a cold rolled 18% Ni maraging steel have been studied to apply a continuous annealing process to austenitization of this type of steel sheet. The results obtained are summarized as follows.
(1) Austenitization of the cold rolled 18% Ni maraging steel can be performed in a continuous annealing line to provide the mechanical property comparable to that obtained in the conventional austenitizing condition of 820°C×1h if the austenitizing temperature is higher than 900°C.
(2) The {111}<uvw> orientations, which strongly developed during cold rolling, gradually change into the near (557)[110] and (554) [156] orientations and the (001)[010] orientation evolves with progress of austenitizing.
(3) A marked hardness increase of about 40% from the as-annealed state was observed in the early stage of aging at 480°C, irrespective of the prior austenitizing conditions.
(4) The number of Fe atoms with Mo neighbors decreases within 3min of aging at 480°C, as evidenced by the Mössbauer spectrometry. The marked hardening in the early stage of aging is suggested to be a result of lattice distortion by clustering of Mo atoms.
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