公开(公告)号：US20230400298A1

公开(公告)日：2023-12-14

申请号：US18033387

申请日：2021-11-02

Applicant: NIPPON STEEL CORPORATION

Inventor： Tooru AKASHI ,  Keita IKEDA ,  Yasumitsu KONDO ,  Naoki INOUE ,  Akinobu MINAMI

IPC: G01B21/08

CPC classification number: G01B21/085

Abstract: This internal oxide layer thickness estimation device estimates a thickness of an internal oxide layer formed in a hot-rolled steel sheet. The internal oxide layer thickness estimation device includes: a first temperature definition unit that defines a temperature of a portion to be estimated, in which the thickness of the internal oxide layer is to be estimated, in the hot-rolled steel sheet; a second temperature definition unit that defines an internal oxidation starting temperature at which internal oxidation of the hot-rolled steel sheet starts; a cumulative temperature calculation unit that calculates a cumulative temperature on the basis of the temperatures defined by the first temperature definition unit and the second temperature definition unit and a predetermined period of time from an estimation start time at which estimation of the thickness of the internal oxide layer is started to an estimation evaluation time; a first correlation expression derivation unit that derives a first correlation expression indicating a correlation between the cumulative temperature calculated by the cumulative temperature calculation unit and an estimated value of the thickness of the internal oxide layer; and an internal oxide layer thickness estimation unit that estimates the thickness of the internal oxide layer on the basis of the first correlation expression.

公开(公告)号：US20220389545A1

公开(公告)日：2022-12-08

申请号：US17295298

申请日：2019-11-20

Applicant: NIPPON STEEL CORPORATION

Inventor： Shohei YABU ,  Kunio HAYASHI ,  Yuji YAMAGUCHI ,  Marina MORI ,  Naoki INOUE ,  Genki ABUKAWA

IPC: C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  C21D8/02 ,  C21D9/46

Abstract: A hot-rolled steel sheet includes, as chemical composition, C, Si, Mn, and sol.Al. In the hot-rolled steel sheet, an average of pole densities in crystal orientation group consisting of {110} to {110} in surface region is 0.5 to 3.0, a standard deviation of the pole densities in the crystal orientation group is 0.2 to 2.0, and the tensile strength is 780 to 1370 MPa.