Low Carbon Bainite High Strength (LCBHS) Structural Steel

Hot Rolled Strip (Coil), in mm	Permissible Dimensional Tolerance
3.0ï½Âž20*11301ï½Âž2150	GB/T709 Applicable

Technical Condition for Supply: Chemical Ingredients (% by Weight)

Grade	C	Si	Mn	P	S	Cu	Nb	B	Mo	Ti	Ni
DB590R	≤0.08	≤0.40	1.30ï½Âž1.70	≤0.025	≤0.015	≤0.35	≤0.06	≤0.003	-	-	-
DB685R	0.02ï½Âž0.08	≤0.50		≤	≤	≤0.25	≤0.06	≤0.003	≤0.30	≤0.03	-
DB685D*	≤0.08	≤0.50	1.30ï½Âž1.80	≤0.030	≤0.025	≤0.70	≤0.10	≤0.003	≤0.35	-	≤0.50
DB685E*

Technical Condition for Supply: Mechanical Performance

Grade	Specification mm	Tensile Test				180° Bending Test	Impact Test
		Rst. Mpa	Ra Mpa	Scale Distance, mm	A%		Temperature, ℃	Direction	Akv J
DB590R	3-10	≥450	570-720	L=50	≥20	d=2a	-40	Longitudinal	≥47
DB685R	4-10	≥590	670-830	L=50	≥17	d=2a	-40	Longitudinal	≥24
DB685D*	4-20	≥590	670-830	Lq=5.65S1/2	≥15	d=2a	-20	Longitudinal	≥47
DB685E*	4-20	≥590	670-830	Lq=5.65S1/2	≥15	d=2a	-40	Longitudinal	≥34

Level of Test Piece: Mechanical Performance

Steel Grade	Specification mm	Tensile Test				180° Bending Test	Impact Test
		Rst. Mpa	Ra Mpa	Scale Distance, in mm	A%		Temperature, ℃	Direction	Akv J
DB590R	3-10	470-635	595-710	L=50	24-30	d=0;perfect	-40	Longitudinal	131-220
DB685R	4-10	590-690	685-770	L=50	23-27	d=0;perfect	-40	Longitudinal	117-242
DB685E*	4-20	590-690	685-770	Lq=5.65S1/2	23-27	d=2a;perfect	-40	Longitudinal	110-220

Note: The steel grades with “*” mark are DB685 series produced by WISCO No. 2 Hot Rolling Mill.