Best advanced steels for efficient bending and forming

Higher profits come from giving customers a better quality material without having to install special tooling or make new equipment investments.

Strenx^® and Hardox^® brand steels have established real results for fabricators, OEMs and end users - trusted by many as the best products on the market.

For example, Strenx^® high-strength structural steel offers guaranteed properties for repeatable bending that's machinable on most workshops’ standard equipment.

This makes bending and forming more efficient with higher consistency and repeatable performance. The material provides tight thickness tolerances, tight flatness tolerances, as well as tight bending guarantees for improved workshop properties. Operators improve safety and efficiency when they can count on the same outcome time after time on the press brake and rolling machines.

What are the key properties of Strenx^® steel?

Strenx performance steel offers guaranteed properties for repeatable bending. The Strenx^® portfolio comes in a wide range of grades including plates, sheets, coils, sections and tubes. Thicknesses range from 0.7 to 160mm with a yield strength between 600 to 1300 MPa. This super-consistent steel is backed by Strenx^® guarantees for flatness, thickness and bendability.

Strenx^® has four bending guarantee classes. Strenx^® guarantees include tight thickness tolerances, tight flatness tolerances and bending guarantees. The tight thickness tolerances enable you to know the weight more precisely. As a result, you can reduce your safety margins. Precise thickness within a plate and between plates makes for safe and predictable performance in the workshop.

Laser cutting and automated welding benefit from the narrow tolerances for optimized cutting speed. When bending, you can use the same force and get the same springback from plate to plate.

Strenx^® steel has extremely consistent properties, ensuring precision and efficiency in the workshop. Yield and tensile strength, bending performance and impact toughness are carefully tested to ensure consistency in every delivery.

What are the key properties of Hardox^® steel?

Hardox^® brand steel provides tight thickness tolerances, tight flatness tolerances, as well as tight bending guarantees for improved workshop properties.

Thanks to its extreme toughness, Hardox^® copes with shocks, jolts, bangs, nicks and jabs, day after day. And with its good workshop properties, you can bend it, form it and weld it, and it will keep resisting cracks and crack propagation without losing its properties. Together with its high yield strength, this allows for lighter designs.

In aggressive environments, where breakage failures can be unpredictable and costly or even threaten the safety of your equipment and people, Hardox^® wear plate helps you minimize the risks so your equipment — and your business — won’t break down.

These steels are only manufactured by SSAB and available from certified partners. SSAB continuously works to improve the production processes in order to develop new and better products. This has resulted in the ability to guarantee both closer tolerances and improved workshop properties.

What's the difference between U-die and V-die bending

Bending steel requires a U-die or a V-die. The V-die is most common for mild steel bending. A press break can still be used on high-strength steel.

The most important thing to consider is the top punch radius, which is the part pressing down on the plate. With high-strength steel, that's what forms the inner radius. If that inner radius is too small, you'll start to see cracking and the grain structure starts to open on the outside surface of the plate.

With air bending, no heat is applied. Mild steel doesn't follow the punch and the radius depends on die width. However, high-strength steel follows the punch and the radius is not dependent on the die width. A larger die width requires less force to bend the piece of plate. A larger die width and thinner material leads to about the same bending force as mild steel.

You can account for springback by overbending. An increase of 100 MPa (14.5 ksi) in yield stress results in about 1 degree more springback.

The over bending angle depends on yield point, bend radius and sheet thickness.

How do I prevent measurement errors in bending parameters?

It's vital to get it right. SSAB provides a handy digital tool to instantly calculate bending parameters for press braking our steels. Check out our free BendCalc mobile app and download from Apple's App Store or Google Play.

Just plug in steel characteristics, die and tool symmetry, final bend shape, and friction conditions to get a instant, precise calculation of bending settings. You can even switch between metric and imperial units to get the correct bending in seconds.

The graph result includes:

• Required bend force
• Opening angle during maximal stroke
• Punch depth
• Springback
• Minimum flange height

Before the result, all values are checked, including minimum values of bending radius and die width. The result can be saved and exported as a pdf report to the press brake operator.

This is the first software to predict real springback and real punch depth with exact results in seconds.

How do you properly bend special steels?

Let's look more closely at the dos and don'ts for proper bending of special steels. All it takes to properly prepare is to use the BendCalc app. You'll have an answer in seconds to keep powering through your project quickly and confidently.

After you have your results, follow this check list:

1. Check the rolling direction.

There are two types of bends: the Hard-way bend, which goes along the rolling direction; and the Easy-way Bend, which is transverse to rolling direction.

When possible, the bending line should be transverse to the rolling direction as smaller bending radii can be used versus along the rolling direction. For long pieces like sidewalls, you have no choice but to bend parallel to the rolling direction.

2. Check the surface condition.

Surface damage can act as crack initiators and cause fractures. Carefully grind away scratches.

3. Check the edge condition.

Thermal cut and especially sheared edges should be deburred and rounded with a grinder prior to bending. If the edge cannot be ground, the burred side should be placed on the inner surface of the bend.

4. Check the tooling and bender set up.

Check the condition of the tools to be sure your tools are in good condition. To avoid excessive tool wear, tooling should be harder than the work piece. Make sure the tools and tool setup are in line with the bending recommendations for Hardox and Strenx.

5. Check the distance between a hole and a bend.

Be careful when bending near holes. If you're too close to the hole when you bend the steel, the hole will be deformed.

Learn more

Dig deeper by watching an insightful on-demand webinar about how to bend and form high-strength steels.

Ready to take the next step in learning more about SSAB steels? Contact one of our customer service representatives today to get started.