Top MIG Welding Wires for Stainless Steel: Which Type is Best for Your Project?

A solid wire that serves as an electrode and a filler substance is necessary for the MIG (metal inert gas) welding procedure. A shielding gas is also required for this operation in order to prevent contamination and oxidation of the weld pool. For MIG welding stainless steel, argon mixtures containing 1%–2% oxygen and tri-mixes of helium, argon, and CO2 are often utilised gases.

Additionally, a filler metal and wire are used as electrodes in the flux-cored welding process. On the other hand, the core of flux-cored wires contains chemical substances that have been carefully prepared. These wires resemble pipes in that they are tubular. The filler metal, which transmits electricity and melts into the welded seam, is only present in the outer layer.

Gas-shielded flux-cored wires are appropriate for welding thick metal and provide greater deposition rates. Additionally, their slag helps retain the molten metal pool against gravity, which makes them ideal for out-of-position welding.

However, the ability to employ common shielding gas mixes like argon/CO2 or pure CO2 is one of the most significant benefits of gas-shielded FCAW wires for welding stainless steel. You may use a regular MIG welding gas for mild steel rather than spending money on an argon/oxygen or tri-mix gas.

The 300 series of austenitic stainless steel is the most widely used and welded stainless steel kind. In general, the stainless steel series you are welding should match the filler metal you choose. For instance, E308LT flux-cored wires or ER308L or ER308LSi solid wires are used to weld 308L stainless steel.

Nonetheless, a filler material with a larger proportion of stainless alloy is sometimes used if an exact match filler metal is not available. For 301, 302, 304, and 305 grades, for instance, a 308 stainless filler wire is utilised.

The most popular stainless steel wires for flux-cored arc and MIG welding are kept in stock by Fortis Metals. Let's look at each and discuss its uses and advantages.

Let's examine the 308LSi stainless steel MIG wire as an example to better understand the categorisation symbols.

The alloy of stainless steel that the wire is made of is indicated by the number 308. Low carbon content (0.03% maximum) is represented by the letter "L," which lowers the likelihood of intergranular carbide precipitation and the ensuing loss of corrosion resistance. The "Si" indicates that the wire contains more silicone, which improves the weld metal's wetting behaviour.

The letter "L" stands for low carbon concentration, just like in MIG wires. The number "1" next to the letter "T" indicates that the wire is an all-position electrode, whereas the letter "T" itself indicates that the wire is in fact flux-cored. The following "1/4" designates the shielding gas: "1" denotes 100% CO2, while "4" denotes a combination of 75–80% argon and 25–20% CO2.

Similar to MIG wires, the character "L" denotes low carbon content. While the letter "T" alone indicates that the wire is flux-cored, the number "1" next to the letter "T" indicates that the wire is an all-position electrode. The shielding gas is indicated by the following "1/4": "1" stands for 100% CO2, and "4" for a mixture of 75–80% argon and 25–20% CO2.

Since stainless steel is a challenging material to weld, Fortis Metals specialists are available to help you select the best stainless steel wire. Submit an online inquiry to talk with an expert.