What is en HARDO X400 equivalent steel material
En HARDO X400 is a specialized alloy steel developed specifically for demanding structural applications. It’s a higher strength alloy that combines excellent mechanical properties with exceptional toughness and wear resistance. Developed by the French steel producer Cogne Specialty Steel, the En HARDO X400 alloy steel is typically used in applications requiring higher strength levels than regular carbon or low-alloy steels can provide. This includes components used in the construction of bridges, offshore structures, and other heavy-duty equipment.
En HARDO X400 is a martensitic-bainitic alloy steel. The martensitic phase improves its strength while the bainitic phase provides high toughness levels. The steel’s high inherent strength is obtained through an optimization of its hardenability. This helps to ensure the steel can be hardened over the entire cross-sectional part of the component, preventing any formation of segregated microstructures with inadequate hardness or toughness.
The composition of En HARDO X400 is aimed at providing the highest levels of strength and toughness. It has a high carbon content of 0.25%-0.33%, along with chromium (1.30%-1.90%), molybdenum (0.72%-1.20%), nickel (0.4%-0.75%), and vanadium (0.15%-0.46%). Furthermore, its General Performance Rules (PCR) classifies it as hardened and tempered corrosion-resistant steel with a medium-high alloy content offering a minimum yield strength of 655 MPa and a minimum tensile strength of 785 Mpa.
Due to its specialized composition, En HARDO X400 offers a full range of mechanical properties. These include excellent fatigue strength, good toughness, and wear resistance. This wear resistance can be further improved with surface hardening processes such as nitriding or carburizing.
When looking for a suitable steel grade that has similar properties to the En HARDO X400 alloy steel, the most suitable and comparable grade is the ASTM A800 grade termed “Cogne X22CrMoV12-1”. This steel grade is also produced by the French company Cogne and has similar strength, toughness, and wear resistance properties. This grade is composed of 1.25-1.40% Carbon, 12.00%-13.50% Chromium, 1.00%-1.50% Molybdenum, 0.20%-0.50% Vanadium, and 0.45%-0.70% Nickel, which also makes it suitable for heavy-duty applications.
In conclusion, En HARDO X400 is a specialized alloy steel designed to offer superior mechanical properties suitable for demanding applications, such as those found in bridges and other offshore structures. It has an optimized composition offering a high level of strength and toughness, and is further suitable to surface hardening. To find an equivalent material, the closest option is the Cogne X22CrMoV12-1 grade from ASTM A800, which is an identical product supplied by the same manufacturer.
