What are common myths about welding advanced high strength steels

Let's start with the most important point: Workshop processes don't need to change for steels like Hardox^® wear steel and Strenx^® performance steel because of their quality, consistency and guarantees.

Advanced high-strength steels (AHSS) present several advantages over mild steel, especially in terms of overall quality and workshop properties, including welding. SSAB manufactures next-generation, high-strength steels to encourage innovation and efficiency. For example, the Hardox^® wear plate portfolio addresses aggressive wear with superior hardness and toughness. The Strenx^® performance steel allows engineers to remove weight and maintain strength for lighter, stronger equipment.

So, it’s easy to see why there may be misconceptions about welding such high-performing materials. Let’s take a closer look.

Can high strength steel be welded?

Due to the unique nature of high-strength steels' manufactured specifications and processes, you might think they would pose welding challenges when compared to mild steels of the same thickness. However, for the majority of the Hardox and Strenx steel ranges, no additional special parameters are required to properly weld these materials.

The Hardox^® wear plate range, which also includes sheet, round bars, pipes and tubes, combines unique performance with exceptional weldability. The extreme performance of Strenx^® high-strength steel is also combined with exceptional weldability. Any conventional welding method can be used for welding Hardox or Strenx to other types of weldable steels.

Distortion behavior for both Stren^® and Hardox^® branded steels is similar to other low alloyed steel. Thinner gauges are more sensitive to welding distortion, similar to all other steel grades.

See more welding recommendations on SSAB's webinar, Common Myths about Welding Special Steels.

SSAB provides digital tools to run your welding parameters through various settings to calculate heat input, risk of hydrogen cracking and softening of the heat affected zone. Check out our WeldCalc 3.0 web app or WeldCalc mobile app. Android or iPhones.

What is advanced high strength steel?

All AHSS steels achieve their high strength by steel producers precisely controlling their chemistries and their heating and cooling rates. These advanced high-strength steels are often used in automotive applications. Many grades meet a minimum tensile strength of 440 MPa (64 ksi or 64,000 psi), according to WorldAutoSteel, the automotive industry association of AHSS steel manufacturers.

Some of the most popular metallurgical types of steels capable of achieving AHSS tensile strengths include:]

• Martensitic (M)
• Press Hardening Steel (PHS, aka hardenable boron steel, aka “hot stamped” steel)
• Complex Phase (CP)
• High Edge Ductility (HE)
• Dual Phase (DP)
• Dual Phase with High Formability (DH)
• Ferritic Bainitic (FB)

As noted, advanced steels manufactured by SSAB offer upgraded performance over mild steel selections. Applications requiring wear resistance and toughness for long life benefit by specifying Hardox^® wear steel. Structural applications demanding high strength but with thinner gauges will reduce overall weight using Strenx^® performance steel.

Can high strength steel be welded to mild steel?

It's important to think through the parameters when joining different grades of steel and materials. In particular, multi-material bodies require some homework. For example, some materials are more noble than others, and have a tendency to corrode when joined in certain ways. In addition, thermal expansion can vary greatly between two materials, which can quickly compromise the welded or bonded joint as temperatures change. Because of these challenges, the materials used and welding parameters must be much more tightly controlled than in the past.

SSAB helps welders get it right the first time with the WeldCalc app that provides set-up parameters based on the job at hand. WeldCalc calculates and presents welding recommendations for both Hardox^® wear plates and Strenx^® performance steels. Based on the welding method, the welding joint, steel grades and thicknesses, it gives you the result in seconds:

• Recommended preheat and interpass temperatures.

• Recommended minimum and maximum heat input.

• Recommended welding machine settings (amps, volts and travel speed).

• Risk analysis.

You can save the results and share the report as PDF. Use it to save the golden arm’s specs for the bugger in training.

Dig deeper by watching an on-demand webinar to get all of the answers to these and other burning questions when it comes to debunking the myths around welding advanced steels.

Learn more by downloading our welding handbook that addresses material technology, industrial engineering and mechanics of materials.