toughcore® is a brand of voestalpine Grobblech GmbH and is distributed by UnionStahl in Western Europe.

Properties of toughcore®

toughcore® defines a new as-delivered condition for thermomechanically rolled heavy plate with the unique combination of strength and excellent toughness down to the core – while offering the optimal weldability.

The innovative production process ensures:

  • High toughness even at low temperatures (CVN down to 80°C)
  • Consistent/homogeneous mechanical properties over the entire plate thickness
  • Fine grain structure over the entire plate thickness
  • Improved values in crack tip opening displacement (CTOD)
  • Improved values in the Battelle drop-weight tear test (BDWTT)
MaterialThickness (mm)Widths (mm)Lengths (mm)
S355 ML toughcore / alform plate S355 M toughcore40 – 1401.500 – 3.800up to 18.700
S420 ML toughcore/ alform plate S420 M toughcore40 – 1401.500 – 3.800up to 18.700
S460 ML toughcore/ alform plate S460 M toughcore40 – 1401.500 – 3.800up to 18.700
S355 MLO thoughcore40 – 1401.500 – 3.800up to 18.700
S420 MLO thoughcore40 – 1401.500 – 3.800up to 18.700
S460 MLO thoughcore40 – 1401.500 – 3.800up to 18.700
durostat 400 toughcore20 – 901.500 – 3.000up to 12.000
durostat 450 toughcore20 – 401.500 – 3.000up to 12.000

Advantages of toughcore®

toughcore® heavy plates offer the following advantages over conventional thermomechanically manufactured steel grades:

  • The steels ensure very high operational reliability while exploiting the potential of heavy plate under extreme conditions, such as very low temperatures or deep-sea applications, with the lowest risk of brittle fracture.
  • In the fields of construction machinery, steel construction, pipelines and offshore, there are opportunities for cost-efficient and weight-reduced design.
  • Optimal welding properties increase productivity – while preheating is no longer necessary for thin plates.
  • At low operating temperatures, durostat® toughcore® plates in particular have 20% higher hardness values and thus better wear properties.
  • Classic QT plates can be replaced by thermomechanically rolled plates to offer much better weldability with significantly lower carbon content as well as improved surface quality for optimal and efficient workability.

toughcore®: strong in these sectors



For maximum operational safety
toughcore® steels ensure maximum reliability for offshore applications. The focus is on the entire supply chain – from exploration and installation to transport and storage. These heavy plates combine the material properties of strength, excellent toughness – even at the lowest temperatures – and optimal weldability. These advantages are retained even by thick plates (up to 140 mm thick).
The trend in platform construction is towards ever larger components and therefore thicker plates as well. toughcore® plates allow the use of higher strength classes with the same toughness. This means that thinner plates can be used for construction – resulting in potential weight and cost savings compared to classic offshore steels. The improved weldability another key benefit.



For extreme cold
For the construction of ice-going ships, toughcore® steels are suitable replacements for conventional shipbuilding steels and are recommended for use in Arctic regions (as high as Arctic Class III with up to 100 mm plate thickness). Exploration of extreme regions is made possible – combined with the advantages of higher safety, potential cost savings, increased productivity and optimal weldability. Damage in ship collisions is minimised due to the higher toughness at low temperatures.


Crane construction

For really high toughness
toughcore® plates offer various advantages for the crane construction industry compared to the steels used up to now. The high toughness – especially at low temperatures – massively increases reliability when used in Arctic regions. The remarkably fine structure of toughcore® heavy plates over the entire cross-section is the reason for the high toughness. Builders also benefit from the exceptional processing properties. For example, there is no need to preheat thin heavy plates at all. The lower carbon content leads to better weldability and significantly reduces susceptibility to cold cracking. Faster welding is possible thanks to higher heat input – while at the same time meeting the specified requirements.



For minimal wear
durostat® toughcore® steels stand for minimal wear and tear and – thanks to their higher resistance – offer the potential for weight savings through the use of thinner plates. What is more, the thermomechanically manufactured steels provide a longer service life for the manufactured components compared to conventionally manufactured wear-resistant steels. This is due to the higher surface hardness and lower removal rates. Toughness at low operating temperatures is guaranteed by the manufacturer for thermomechanical steels. Another advantage for fabricators is the excellent surface quality, which makes machining easier. Good weldability means that preheating is no longer necessary for thin plates.


Steel construction

For state-of-the-art design
Maximum toughness and high strength at low temperatures combined with optimal weldability makes for considerable advantages in this industry too. These properties allow for improvements in the building design. Imagine slim and seemingly delicate building structures with enhanced aesthetics and ultra-modern design up to the highest heights. The low risk of brittle fracture ensures increased component reliability.


Container construction

For new possibilities
In the area of container construction, the use of toughcore® steels opens up new applications for fabricators. They main advantages are the high toughness at low temperatures and excellent weldability, plus the high operational reliability.
One example application is LPG tank production. Compared to the steel grades previously used here, the reduced nickel content results in a cost benefit. Another potential advantage is a reduction in the carbon footprint of tank production thanks to the sustainable alloy concept.


Pipeline construction

For extreme loads
Today’s pipelines have to withstand increasingly severe extremes – whether they are laid in ultra-deep water or in Arctic regions. toughcore® heavy plates offer significant advantages here over conventional linepipe steels and high-strength steels thanks to their excellent toughness at temperatures down to 80°C. The risk of brittle fracture under these adverse environmental conditions is reduced. The pipes can withstand the highest pressures.
Production of the crack arrestors from toughcore® ensures the highest operational reliability.
Other positive effects include higher productivity due to increased flow rates resulting from thicker walls which support larger pipe diameters, reduced welding costs thanks to the possibility of higher heat input during welding, plus weight reduction and the associated cost savings.