Al dente shaped bar steel (Surface-layer softened steel) is heat treated bar steel with arbitrarily adjusted hardness along the cross sectional direction of the bar steel. (Patented)
- Thanks to significant improvement in the HE characteristics (hydrogen embrittlement), delayed fracture resistance is enhanced while maintaining high strength.
- Softened outer surface provides outstanding surface machining properties
(1) The softened layer has fewer hydrogen trapping sites and is less prone to crack initiation.
(2) No transgranular film-like carbides provides no transgranular delamination.
References:Y.Matsumoto,K.Takai,M,Ichiba,T.Suzuki,T.Okamura and S.Mizoguchi:Tetsu-to-Hagane,99(2013),236
Wire diameter: 7.0 to 40.0 mm
Product form: bar shape (max. 12 m) or coil shape (max. 2 tons)
Tensile strength: 1,230 to 1,420 N/mm2 or higher (standard value)
★ Excellent delayed fracture resistance
★Improves rolling tool life by 1.5 times (superior machining property)
Compared to our products
Size : φ5 to φ40 mm
Steel types: S35C and other structural steels, spring steels, stainless steels (hardenable bars)
Approximate strength (tensile strength): 1,200 to 2,200 N/mm².
High-strength bolt (prototype)
Size: M12
Strength class: 14.9 equivalent
Tensile strength: 1,500 N/mm² (base material)
High stress spring (prototype)
Size: Height 300, inner diameter φ75, total number of coil turns 8, wire diameter φ12
Tensile strength: 2,150 N/mm² (wire)
