62071200 - Bonarc ER308LSi .045" Stainless MIG Wire - 12kg Spool

High-Performance Austenitic Stainless Steel Consumable

The Bonarc ER308LSi .045" Stainless Steel MIG Wire is a premium-grade solid welding wire designed for the Gas Metal Arc Welding (GMAW) process. It is specifically formulated to join austenitic stainless steels of the 18% Chromium - 8% Nickel variety, most notably AISI grades 301, 302, 304, and 304L. The "Si" designation in the AWS classification indicates a higher silicon content (typically 0.65% to 1.00%) compared to standard ER308L wires. This elevated silicon level serves as a deoxidizer and significantly enhances the wetting action of the molten weld pool. Consequently, operators experience a more fluid puddle that washes into the toes of the weld smoothly, creating a flat, aesthetically pleasing bead profile with minimal post-weld grinding requirements.

In addition to its superior wetting characteristics, this wire maintains the "L" or Low Carbon classification, with carbon content restricted to a maximum of 0.03%. This critical chemical composition minimizes the risk of carbide precipitation at the grain boundaries during the welding process, thereby preserving the material's resistance to intergranular corrosion. This makes the Bonarc ER308LSi an ideal choice for applications in corrosive environments where structural integrity and longevity are essential. The wire is manufactured to strict tolerances, ensuring consistent diameter and surface finish, which translates to stable electrical conductivity and reliable feeding through standard MIG gun liners.

Technical Application and Specifications

This 0.045-inch (1.2mm) diameter wire is well-suited for medium-to-heavy gauge fabrication, allowing for higher deposition rates and increased travel speeds compared to smaller diameters. It is designed for use with Direct Current Electrode Positive (DCEP) polarity. The recommended shielding gas is a mixture of Argon and CO2 (typically 98% Ar / 2% CO2) or an Argon/Oxygen mix (98% Ar / 2% O2). For applications requiring specific bead colors or penetration profiles, helium-based tri-mix gases may also be utilized. The 12kg (26.5 lb) spool is a standard industrial size, compatible with most wire feeders found in fabrication shops, reducing downtime associated with frequent spool changes.

Mechanical properties of the weld metal typically exhibit a tensile strength exceeding 550 MPa and elongation greater than 35%, meeting the rigorous demands of structural stainless steel fabrication. Proper storage in a dry, low-humidity environment is recommended to prevent surface contamination prior to use. This wire is not recommended for welding high-carbon stainless steels where high-temperature strength is the primary concern, nor is it suitable for joining stainless steel to carbon steel (where ER309L would be preferred).