EN10025-6 S690QL1 steel

EN10025-6 specifies requirements for flat products of high yield strength alloy special steels. The qualities of S690QL1 are given in the below tables (chemical composition and mechanical properties), and S690QL is supplied in the quenched and tempered condition. EN10025-6 S690QL1 specified in the standard are applicable to hot-rolled flat products with a minimum nominal thickness of 3 mm and a maximum nominal thickness ≤ 150 mm, and after quenching and tempering, EN10025-6 S690QL1 has a specified minimum yield strength of 690MPa.

EN10025-6 S690QL1 Chemical Composition   

Grade	Chemical Composition
S690QL1	The Element Max (%)
	C	Si	Mn	P	S	Nb	V	Ti	Zr	Cr	Ni	Mo	Cu	N
	0.22	0.86	1.80	0.025	0.012	0.07	0.14	0.07	0.17	1.60	2.1	0.74	0.55	0.016

                                                           

EN10025-6 S690QL1 Mechanical Property

Grade	Mechanical Property
S690QL1	Yield Strength mm Min(Mpa)			Tensile Strength mm Min(Mpa)			Elongation Min,%
	≥ 3 ≤ 50	＞ 50 ≤ 100	＞ 100 ≤ 150	≥ 3 ≤ 50	＞ 50 ≤ 100	＞ 100 ≤ 150
	690	650	630	770-940	760-930	710-900	14

EN10025-6 S690QL1 does not have unlimited suitability for the various welding processes, since the behaviour of a steel during and after welding depends not only on the material but also on the dimensions and shape and on the manufacturing and service conditions of the components. With increasing product thickness and strength level cold cracking can occur. Cold cracking is caused by the following factors in combination:
− the amount of diffusible hydrogen in the weld metal;
− a brittle structure of the heat affected zone;
− significant tensile stress concentrations in the welded joint.