Differences between S890QL and S890QL1
As ultra - high - strength quenched and tempered structural steels complying with the EN10025 - 6 European standard, S890QL and S890QL1 both have a minimum yield strength of 890MPa for plates with thickness ≤50mm. However, they are distinctly different in low - temperature toughness, chemical composition optimization, application scenarios and supply methods, which makes them suitable for different working conditions. The specific differences are as follows:
Low - temperature toughness
Key gap in impact temperature resistance
The core difference lies in their low - temperature impact performance indicators. The "L" in S890QL indicates that it can maintain a specified minimum impact energy at a temperature not lower than -50℃. In contrast, the "L1" in S890QL1 represents enhanced low - temperature adaptability, which can meet the impact toughness requirements at -60℃. This 10℃ lower temperature resistance threshold means S890QL1 can avoid brittle fracture risks better in extreme cold environments, while S890QL may lose stable toughness when exposed to temperatures below -50℃.
Chemical composition
Fine - tuning for extreme performance
Both steels adopt low - carbon alloy formulas, but S890QL1 has optimized alloy proportions to enhance ultra - low - temperature performance. For S890QL, its chemical composition includes elements such as chromium, nickel and molybdenum in moderate amounts to balance strength and toughness at -50℃. S890QL1 adjusts elements like nickel (which boosts low - temperature toughness) and strictly controls impurity content (phosphorus ≤0.020%, sulfur ≤0.010%). This fine - tuning avoids the toughness decline caused by impurities in ultra - low temperatures and achieves a better balance between strength and extreme cold resistance that S890QL does not possess.
Application scenarios
Differentiation based on cold resistance demands
S890QL is widely used in general low - temperature and high - load fields. It is applied to crane structural parts, hydraulic props, bridge main beams and ship structural components, and is also suitable for offshore platforms in temperate seas and mining equipment in regions with mild cold climates. S890QL1 targets more harsh extremely cold scenarios, such as structural parts of oil drilling platforms in the Arctic/Antarctic, wind turbine towers in high - altitude cold areas like the Qinghai - Tibet Plateau, and mining truck compartments in frigid mining areas such as Siberia. These scenarios require resistance to continuous stress and low - temperature embrittlement.
Supply and processing
Differences in customization and adaptability
S890QL has mature production technology and sufficient spot supplies in the market. It can be supplied in multiple specifications and is easy to cut, weld and form, suitable for mass - produced engineering components. S890QL1, due to its strict requirements for ultra - low - temperature performance, has fewer spot products. It is usually supplied by custom rolling according to customer engineering needs. Although both have good weldability, S890QL1 requires more precise control of preheating and interlayer temperatures during welding to ensure its ultra - low - temperature performance remains intact.
Is S890QL1 more expensive than S890Q?
Yes-S890QL1 costs ~25% more due to stricter alloying (e.g., extra Ni) and low-temperature processing.
Can S890Q replace S890QL in cold areas?
No-S890Q lacks -50°C impact resistance, risking cracking in frigid conditions.
What industries use S890QL1 most?
Polar oil platforms, alpine pipeline structures, and Arctic mining equipment rely on its -60°C resilience.