Invention Grant
- Patent Title: 700Mpa-level high-strength hot rolling Q and P steel and manufacturing method thereof
-
Application No.: US14769647Application Date: 2014-03-13
-
Publication No.: US10023928B2Publication Date: 2018-07-17
- Inventor: Huanrong Wang , Zigang Li , Wei Wang , Jiansu Zhang , Jianye Li
- Applicant: BAOSHAN IRON & STEEL CO., LTD.
- Applicant Address: CN Shanghai
- Assignee: Baoshan Iron & Steel Co., Ltd.
- Current Assignee: Baoshan Iron & Steel Co., Ltd.
- Current Assignee Address: CN Shanghai
- Agency: Quarles & Brady LLP
- Priority: CN201310121568 20130409
- International Application: PCT/CN2014/073344 WO 20140313
- International Announcement: WO2014/166323 WO 20141016
- Main IPC: C21D1/84
- IPC: C21D1/84 ; C22C38/02 ; C22C38/04 ; C22C38/06 ; C22C38/14 ; C21D8/02 ; C21D6/00 ; C21D7/13 ; C21D8/00 ; C22C33/04 ; C22C38/00 ; C21D9/46

Abstract:
A 700 Mpa-level high-strength hot rolling Q&P steel and the method of manufacturing the same, which steel has the chemical compositions in weight percentage as follows: C: 0.15%˜0.40%; Si: 1.0%˜2.0%; Mn: 1.5%˜3.0%; P: less than or equal to 0.015%; S: less than or equal to 0.005%; Al: 0.3%˜1.0%; N: less than or equal to 0.006%; Ti: 0.005%˜0.015%, the remainders being Fe; it having a yield strength of more than or equal to 700 Mpa, a tensile strength of more than or equal to 1300 Mpa and an elongation rate of more than 10%. Through reasonable design on the compositions and on the basis of the compositions of common C—Mn steel, the present invention improves the content of Si to restrict the precipitation of cementite, performs the micro-Ti treatment to refine the austenite grains, and improves the content of Al to quicken the austenite transformation dynamics during the air cooling process; at the same time, combines the hot rolling process with the staged cooling process to obtain the structures of proeutectoid ferrite plus martensite plus retained austenite and reduces the cost of alloy elements substantially.
Public/Granted literature
- US20160017449A1 700MPA-Level High-Strength Hot Rolling Q&P Steel And Method Of Manufacturing The Same Public/Granted day:2016-01-21
Information query