US 12,281,369 B2
Extra thick hot rolled h section steel and production method therefor
Meng Xia, Maanshan (CN); Baoqiao Wu, Maanshan (CN); Meizhuang Wu, Maanshan (CN); Jun Xing, Maanshan (CN); Jie Wang, Maanshan (CN); Hui Chen, Maanshan (CN); Jingcheng Yan, Maanshan (CN); Qi Huang, Maanshan (CN); Lin Peng, Maanshan (CN); Junwei He, Maanshan (CN); Zhaohui Ding, Maanshan (CN); and Qiancheng Shen, Maanshan (CN)
Assigned to MAANSHAN IRON & STEEL CO., LTD., Maanshan (CN)
Appl. No. 18/258,780
Filed by MAANSHAN IRON & STEEL CO., LTD., Maanshan (CN)
PCT Filed Oct. 27, 2021, PCT No. PCT/CN2021/126546
§ 371(c)(1), (2) Date Jun. 21, 2023,
PCT Pub. No. WO2022/095761, PCT Pub. Date May 12, 2022.
Claims priority of application No. 202011217422.6 (CN), filed on Nov. 4, 2020.
Prior Publication US 2024/0110255 A1, Apr. 4, 2024
Int. Cl. C21D 1/18 (2006.01); B21B 1/088 (2006.01); C21D 1/84 (2006.01); C21D 6/00 (2006.01); C21D 8/00 (2006.01); C21D 9/00 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/42 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01)
CPC C21D 9/0068 (2013.01) [B21B 1/088 (2013.01); C21D 1/18 (2013.01); C21D 1/84 (2013.01); C21D 6/004 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/005 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/42 (2013.01); C22C 38/46 (2013.01); C22C 38/48 (2013.01); C22C 38/50 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An extra thick hot rolled H section steel, containing, by mass, the following chemical components: 0.04-0.11% of C, 0.10-0.40% of Si, 0.40-1.00% of Mn, 0.40-1.00% of Cr, 0.10-0.40% of Cu, 0.020-0.060% of Nb, 0.040-0.100% of V, 0.010-0.025% of Ti, 0.010-0.030% of Al, 0.0060-0.0120% of N, not more than 0.015% of P, not more than 0.005% of S, not more than 0.0060% of O, and the balance Fe and trace residual elements, wherein 0.090%<Nb+V+Ti≤0.170%, 6.5≤(V+Ti)/N≤10.5, and the chemical components satisfy the condition of 0.30%≤CEV≤0.48% according to a calculation equation CEV=C+Mn/6+ (Cr+Mo+V)/5+ (Ni+Cu)/15,
wherein at the part, one sixth of the width distance from an end portion and one quarter of the thickness from outer surface, of a flange of the H section steel, a microstructure contains, by area, 85-98% of acicular ferrite and the balance bainite or retained austenite, wherein the bainite content is not more than 2%, the length-width ratio of acicular ferrite is 2:1 to 5:1, and the ferrite has a grain width size of not more than 40 μm, and the difference of acicular ferrite contents in different zones through thickness of the flange is not more than 16%,
wherein the H section steel has a flange thickness of 90 mm-150 mm, and
wherein at the part, one sixth of the width distance from the end portion and one quarter of the thickness from outer surface, of the flange of the H section steel, the tensile yield strength at the room temperature is not less than 460 MPa, the tensile strength is not less than 540 MPa, an elongation after fracture is not less than 24.0%, the impact energy value at −20° C. is not less than 80 J, and the thickness-direction properties reach grade Z35.