公开(公告)号：US11225697B2

公开(公告)日：2022-01-18

申请号：US14974628

申请日：2015-12-18

Applicant: NUCOR CORPORATION

Inventor： James W. Watson ,  Paul Kelly ,  David C. Van Aken ,  Christopher Ronald Killmore

IPC: C21D8/02 ,  B22D11/00 ,  B22D11/06 ,  C21D6/00 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/20 ,  C22C38/22 ,  C22C38/26 ,  C22C38/38

Abstract: A hot rolled light-gauge martensitic steel sheet made by the steps comprising: (a) preparing a molten steel melt comprising: (i) by weight, between 0.20% and 0.35% carbon, less than 1.0% chromium, between 0.7% and 2.0% manganese, between 0.10% and 0.50% silicon, between 0.1% and 1.0% copper, less than 0.05% niobium, less than 0.5% molybdenum, and silicon killed containing less than 0.01% aluminum, and (ii) the remainder iron and impurities resulting from melting; (b) solidifying at a heat flux greater than 10.0 MW/m2 and cooling the molten melt into a steel sheet less than 2.0 mm in thickness in a non-oxidizing atmosphere to below 1080° C. and above Ar3 temperature at a cooling rate greater than 15° C./s; and (c) hot rolling the steel sheet to between 15% and 50% reduction and rapidly cooling.

公开(公告)号：US10995387B2

公开(公告)日：2021-05-04

申请号：US16204129

申请日：2018-11-29

Applicant: NUCOR CORPORATION

Inventor： James W. Watson ,  Tao Wang ,  Eric Young ,  Chad Baudendistel

IPC: C21D9/52 ,  C22C38/04 ,  B22D11/06 ,  C21D1/18 ,  C21D8/02 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/42 ,  C22C38/46 ,  C22C38/48 ,  C22C38/58

Abstract: A weathering steel made by preparing a molten melt producing an as-cast carbon alloy steel strip with a corrosion index of at least 6.0 comprising, by weight, 0.02%-0.08% carbon,

公开(公告)号：US10174398B2

公开(公告)日：2019-01-08

申请号：US15049461

申请日：2016-02-22

Applicant: Nucor Corporation

Inventor： James W. Watson ,  Tao Wang ,  Eric Young ,  Chad Baudendistel

IPC: C22C38/42 ,  C22C38/48 ,  C22C38/58 ,  C21D8/02 ,  C21D9/52 ,  B22D11/06 ,  B22D11/11 ,  B22D11/113 ,  C21D1/18 ,  C22C38/00 ,  C22C38/02 ,  C22C38/06 ,  C22C38/46

Abstract: A method of making weathering steel by preparing a molten melt producing an as-cast carbon alloy steel strip with a corrosion index of at least 6.0 comprising, by weight, 0.02%-0.08% carbon,

公开(公告)号：US11655519B2

公开(公告)日：2023-05-23

申请号：US16488437

申请日：2018-02-27

Applicant: NUCOR CORPORATION

Inventor： James W. Watson ,  Paul Kelly ,  Mike Schueren ,  Walter N. Blejde

IPC: C21D9/52 ,  C22C38/48 ,  C22C38/44 ,  C22C38/42 ,  C22C38/06 ,  C22C38/04 ,  C22C38/02 ,  B22D11/00 ,  B22D11/06 ,  B22D11/12 ,  C21D6/00 ,  C21D1/18 ,  C22C38/46

CPC classification number: C21D9/52 ,  B22D11/001 ,  B22D11/0622 ,  B22D11/1213 ,  C21D1/18 ,  C21D6/004 ,  C21D6/005 ,  C21D6/008 ,  C22C38/02 ,  C22C38/04 ,  C22C38/06 ,  C22C38/42 ,  C22C38/44 ,  C22C38/46 ,  C22C38/48 ,  C21D2211/008

Abstract: This application discloses thin metal strips and methods of making thin metal strip. Particular embodiments of such methods include cooling the thin metal strip to a temperature equal to or less than a bainite or a martensite start transformation temperature BS or MS to thereby form bainite and/or martensite, respectively, within the thin metal strip, reheating the thin metal strip to a reheat temperature equal to or greater than transformation temperature Ac3 and holding the thin metal strip at the reheat temperature for at least 2 seconds and thereby forming austenite within the thin metal strip with at least 75% of austenite grains having a grain size equal to or less than 15 μm, and rapidly recooling the thin metal strip to a temperature equal to or less than the martensite start transformation temperature MS and thereby providing finer martensite within the thin metal strip from a finer prior austenite.

公开(公告)号：US20170327925A1

公开(公告)日：2017-11-16

申请号：US15592679

申请日：2017-05-11

Applicant: NUCOR CORPORATION

Inventor： James W. Watson ,  Harold Bradley Rees

IPC: C21D9/52 ,  C21D8/02 ,  C21D1/667 ,  B22D11/22 ,  B22D11/124 ,  B22D11/06 ,  B22D11/14 ,  C21D9/00 ,  B21B1/22

CPC classification number: C21D9/52 ,  B21B1/22 ,  B21B2001/225 ,  B22D11/0622 ,  B22D11/064 ,  B22D11/0682 ,  B22D11/1246 ,  B22D11/142 ,  B22D11/225 ,  C21D1/667 ,  C21D8/0226 ,  C21D9/0062 ,  G01J1/0252 ,  G01K5/48 ,  G01N25/72

Abstract: To achieve a substantially uniform microstructure across a continuously cast thin metal strip, it is beneficial to cool a width of the strip to a substantially constant temperature before further cooling the strip to reach any desired phase transformation temperature. Accordingly, methods of continuously casting a thin metal strip may include moving the thin strip to a cooling section, the cooling section having a plurality of coolant discharge ports configured to discharge a flow of coolant along the thin strip; initially sensing the temperature of the thin strip to determine a temperature distribution across the width of the thin strip, and producing a sensor signal corresponding to a sensed temperature at each of the first plurality of locations; and individually controlling the cooling across a width of the thin strip by way of the plurality coolant discharge ports in each zone of a first row using the determined temperature distribution.