Stainless Steels for Welding, Part 2

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Stainless Steels for Welding, Part 2

steel

In part one of this two-part blog, we went over ferritic stainless steel and austenitic stainless steel – two types that are potentially highly useful in welding applications. Not all stainless steel grades are weldable to quite the same degree, and a knowledge of which are and aren’t weldable is important in this area.

At Wasatch Steel, our professionals are always here to help in this area. Here’s a look at a few other stainless steel grades that might be great for your next project involving welding.

Martensitic Stainless Steels

Due to their higher carbon content, martensitic stainless steels can be a bit tougher in the welding world than ferritic or austenitic types. More carbon combined with other alloying elements leads to higher chances of a brittle microstructure forming, which can in turn lead to cracking.

There are some precautions that can be taken to prevent this, however. Including as little hydrogen as possible in the welding process is important – hydrogen is often what cracks. If possible, also look to preheat and post-weld treatments to help reduce weld joint brittleness in the heat-affected areas.

Grades 403, 410 and 420 of martensitic stainless steel are great for welding when you have the right filler materials. At the same time, though, many other martensitic grades are considered impossible to weld and you should avoid these. Our pros can help if needed.

Duplex Stainless Steel

Duplex stainless steel refers to steel that’s part austenite and part ferrite in the way it’s composed. It’s made using a complex chemical process, generally with lower chromium levels than other stainless steel types. You’ll need to match filler materials to different types – grade 2205 needs to be welded with grade 2209 filler material, for instance. Again, our steel professionals can guide you in the right direction here.

Precipitation Hardening Stainless Steel

These are steels that gain strength and hardness from intermetallic precipitates that block dislocation in microstructure. You can use a special form of heat treating to form these precipitates, but in welding, these materials can be compromised without the right techniques. To avoid this, you have to heat treat these materials again after the welding. Good steels here include 17-4PH and 17-7PH. Like with duplex stainless steel, filler material is important.

For more on the types of steel that work best for welding, or to learn more about any of our steel services, speak to the pros at Wasatch Steel today.