Steel is one of the most common metals used in welding. Combining iron with 2% of other elements creates steel.
Carbon steel is the most common, with a higher carbon content creating a stronger steel. Steel can be used with virtually any welding process, so why would you need help selecting the best steel for welding?
Because many projects demand stainless steel use. While stainless offers a range of options, some of them are not very good for welding.
When Stainless Can Be the Best Steel for Welding
Stainless steel comes in several varieties, each with strengths and weaknesses. When you shop for stainless steel, you will see:
1. Austenitic Stainless Steel
With standard, low- and high-carbon options, austenitics are the most commonly used stainless steels in welding applications. Low-carbon stainless steel, indicated with a letter L after the grade number, avoids the potential for carbide precipitation, which can cause corrosion.
2. Ferritic Stainless Steel
This type of stainless steel is not a great option for welding. A high carbon content means that this type of stainless steel can lose ductility and strength when heated for welding. It’s best to avoid this group entirely.
3. Martensitic Stainless Steel
If you need a steel with extra hardness, strength, and wear resistance, martensitic stainless steel might be the right choice. This stainless steel option is almost as easy to weld as austenitic options but adds the option to use heat hardening processes. You might need to pre- and post-treat martensitic stainless steel for welding.
4. Duplex Stainless Steel
It may surprise you to know that by combining ferritic and austenitic stainless steel, you double the yield strength and get a weldable metal. Duplex stainless steel is that mix. Duplex stainless steel has better toughness and ductility than ferritic, but it falls just a little short of austenitic.
Choosing Your Steel
What you’re using the finished product for will inform your decision about which steel to use when welding.
If you need something that will last and perform well in seawater, you probably want austenitic or duplex stainless steel. If you want the best corrosion resistance, you want austenitic. Austenitic is not just the most commonly welded stainless steel, it is also the most commonly produced stainless steel.
Don’t need stainless steel’s aesthetic and hygienic properties for your finished product? Carbon steel welds beautifully. So if you don’t need the properties of stainless steel, go for carbon steel. If you insist on using fickle aluminum, check out these tips before you specify a weld.