100996 - Central Wire ER308LSi .030" Stainless MIG Wire - 10lb Spool

Technical Overview: ER308LSi Stainless MIG Wire

The CWM308LSI030-10 is a solid bare wire electrode from Central Wire, classified as ER308LSi under AWS A5.9 standards. This consumable is designed for Gas Metal Arc Welding (GMAW) of austenitic stainless steels, specifically types 304, 304L, 308, and 308L. The wire features a diameter of 0.030 inches (0.8mm) and comes on a standard 10 lb (4.54 kg) spool, making it compatible with most industrial wire feeders and portable MIG welding units.

The "Si" Advantage: Wetting and Fluidity

The primary technical differentiator of this alloy is its high silicon content (typically 0.65% - 1.00%). In stainless steel welding, weld pool sluggishness can be a challenge, often leading to high-crowned beads and poor tie-in at the toes of the weld. The increased silicon in ER308LSi lowers the surface tension of the molten pool, significantly improving wetting action. This allows for faster travel speeds and produces a flatter bead profile with smooth transitions to the base metal. For applications where cosmetic appearance is paramount or where post-weld grinding must be minimized, ER308LSi is the superior choice over standard ER308L.

Metallurgical Properties and Corrosion Resistance

Despite the added silicon, this wire maintains the "L" (Low Carbon) designation, with carbon content capped at 0.03%. This low carbon level is essential for preventing intergranular corrosion (sensitization) caused by chromium carbide precipitation during the welding thermal cycle. The deposited weld metal exhibits excellent resistance to general corrosion and pitting, matching the properties of the 304L base material. The alloy typically provides a tensile strength of approximately 87,000 PSI and elongation of 35%, ensuring ductile and robust joints.

Operational Parameters

For optimal results, this wire should be used with Direct Current Electrode Positive (DCEP). Shielding gas selection is critical for arc stability and weld quality. A mixture of 98% Argon / 2% Oxygen is commonly recommended to enhance arc stability and fluidity further. Alternatively, Argon/CO2 mixtures (with CO2 limited to 2-5%) can be used to prevent carbon pickup while providing good penetration. The 0.030" diameter allows for welding on materials as thin as 18 gauge while still capable of multi-pass welding on thicker sections.