ISO 683-2 Grade 39MnB5

Want to keep this datasheet? Save it now in your required format


Quenchable boron steel represent a breakthrough in heat treatment technology. This steel uses boron as a hardening agent. The melting and refining process, together with thermomechanical treatment by controlled hot rolling, allow ArcelorMittal quenchable boron steel to attain a remarkable degree of hardness and a very uniform microstructure, resulting in excellent mechanical loading performance after heat treatment of the finished part.

Related Standards

Equivalent Materials

This material data has been provided by ArcelorMittal.

"Typical" values were obtained via a literature search. "Predicted" values were imputed via artificial intelligence technology. While we have placed significant efforts in ensuring data accuracy, "typical" and "predicted" data should be considered indicative and verified by appropriate material testing. Please do contact us if additional information on the the predicted data method is required.
All metrics apply to room temperature unless otherwise stated. SI units used unless otherwise stated.
Equivalent standards are similar to one or more standards provided by the supplier. Some equivalent standards may be stricter whereas others may be outside the bounds of the original standard.

Ashby charts





Please feel free to check the figure on the right side of the material page for more details.

Chemical properties



0.0008 - 0.005 %

Show Supplier Material materials with Boron of 0.0008 - 0.005 %


0.36 - 0.42 %

Show Supplier Material materials with Carbon of 0.36 - 0.42 %


1.15 - 1.45 %

Show Supplier Material materials with Manganese of 1.15 - 1.45 %


0.025 %

Show Supplier Material materials with Phosphorus of 0.025 %



0.4 %

Show Supplier Material materials with Silicon of 0.4 %



0.035 %

Show Supplier Material materials with Sulfur of 0.035 %


Technological properties

Application areas

Quenchable boron steel is used in applications requiring good wear resistant properties. The main applications for these steel grades after heat treatment are agricultural machinery (discs, plough shares), machinery for public works and mining, cutting equipment, tubes for automotive safety parts etc. A popular application for untreated steel is concrete mixer drums.

Chemical composition

This grade receives a globularisation treatment of the manganese sulphides. The efficiency of boron is ensured by the addition of elements that bind nitrogen.

Delivery condtion

In spite of their moderate hardness and mechanical properties, boron grades exhibit remarkably good abrasion resistance in their delivery condition, thanks to their composite microstructure consisting of a hard pearlite phase embedded in ferrite. They are therefore very cost-effective solutions for applications requiring good abrasion resistance.


The fatigue resistance of ArcelorMittal's boron quenchable steels is between 40 and 60% higher than S355MC AM FCE low alloy grade. It can be reduced by over 30% if total decarburisation is carried out.

Surface condition

This boron grade is available in A unexposed surface quality only.