Customer case

A bright future for turned, ground and polished Hardox® bright steel bars

July 27, 2020 6 min read

Case details

Product Hardox® Round bar

Country Germany

Company WSB

Industry Industrial production products

Hardox® round bars make an ideal solution in applications that must withstand major stress and wear. They help customers around the world shorten production times and improve the performance of mechanical equipment. Now, high-accuracy Hardox® round bars can be used in even more high-precision, tighter-tolerance applications as turned, ground and polished (TG&P) steel bars, thanks to renowned German machining center WSB.

Engineering components subjected to high stress levels are traditionally hardened by heat treatment. But this only affects the surface of the material and fails to penetrate down to the core. Hardox® round bars are through hardened already when delivered. The hardness is consistent from the surface right down to the core of the material.

Hardox® round bars can be turned to very tight tolerances and remain fully hardened after the turning process. The German turning center Westfälisches Schäl- und Blankstahlzentrum (WSB) has shown that pre-turning of the bars rarely reaches temperature transfers of more than 40°C (104°F) to obtain an average measuring tolerance of an h8 tolerance or h9 tolerance finish. SSAB guarantees the properties of Hardox® steel up to a heat transfer of 250°C (482°F).

Efficient machining systems at WSB enable turned, ground and polished steel bars that meet h9 tolerances.

Case details

Product Hardox® Round bar

Country Germany

Company WSB

Industry Industrial production products

Easy to machine despite their hardness

Machining Hardox® round bars is a highly consistent procedure, thanks to the material’s tightly controlled chemical and mechanical properties. Bolts, threaded bolts and other components are easy to produce. High hardness and yield strength give predictable performance for a wide range of stationary and mobile production machinery.

The steel’s low carbon equivalent results in high toughness and predictable welding performance. The round steel bars are available with diameters ranging from 40 to 100 mm (1.575” - 3.937”). Diameters of 13 to 160 mm (0.152”-6.299”) are currently available as development round bars with AR 400 and AR 500 designation.

Bolts, threaded bolts and other components are easy to produce with Hardox® round bar.

What are bright steel bars?

Bright steel bars are steel bars whose surface has been enhanced by finishing processes like TG&P to produce a smooth, shiny surface without scale, a geometrically precise shape and tighter dimensional tolerances.

The turning process creates a straight round bar without the strain induced by cold drawing. Excellent straightness is crucial in high-speed applications for reducing wear on bearings and preventing vibration. Grinding and polishing improve the finish and roundness of the bar for high dimensional accuracy.

Because of these qualities, bright steel bars like TG&P Hardox® round bars help design engineers reduce the time and cost of manufacture and boost product performance. This makes them a highly versatile choice across a wide range of industries.

High-quality round bars – and high level of accuracy – delivered to your doorstep

Round steel bars produced by SSAB have a high level of accuracy already on delivery. When tighter tolerances are needed for bars in turned, ground and polished steel, SSAB works with machining partners such as WSB.

When WSB got the opportunity to demonstrate its expertise in turning round steel bars, the company already had experience from working Hardox® wear steel

“We had a look at the chemical composition and mechanical properties and quickly realized that we would not have issues with machining,” says Ralf Eckmann, managing director at WSB.

WSB’s outstanding pre-turning system, sawing lines, chamfering systems and the Förster Circograph ensure the required quality – a h9 tolerance in this case. The bright round bars produced were then supplied to a company that manufactures mobile equipment.

Order trial material

WSB’s warehousing capacities guarantee a smooth material process and an efficient material flow to customers. The customers can request their material whenever they need it.

Skip the heat treatment – Hardox® an alternative to conventional materials

High-carbon steels are traditionally used in demanding abrasion-resistant and high-strength applications. But steels such as 42CrMo4V (4140) pose some serious limitations. The typical hardness levels are 28 - 32 RC. Yet increasing the hardness by heat treatment can significantly lower the steel’s crack and fatigue resistance. This can result in premature failure in applications subjected to extreme wear.

Heat treatment as such is always a problem. It is time-consuming, increases costs and, above all, represents a risk factor, since the quality of the component after heat treatment remains unclear.

And this risk increases because the origin of the steel and the quality control procedures are often unknown. This may be crucial when product guarantees are needed.

Bright steel bars in Hardox® wear steel offer a better solution. For starters, they are made from exceptionally clean steel in a carefully controlled production process. The consistency of the material ensures predictable performance both in the workshop and as machine components in demanding applications. High hardness gives a longer service life, while the yield and tensile strengths guarantee a low risk of premature failure.

*The data in this table are typical values

Uses for Hardox® bright steel round bars

Hardox® wear plate has set the standard for premium wear-resistant steel for decades. The same combination of properties – consistency, hardness, toughness, machinability and weldability –make Hardox® round bars a natural choice for demanding wear applications such as these: