Types of Filler Wire for MIG Welding

Types of Filler Wire for MIG Welding

MIG welding is a versatile welding technique widely used for various materials such as carbon steel, stainless steel, and aluminum. The selection of filler wire is crucial to achieve the desired welding quality, strength, and durability. This article delves into the different types of filler wire used for MIG welding, their properties, and applications.

Carbon Steel Filler Wire: ERS-70–6

When working with carbon steel, one common choice for filler wire is the ERS-70–6. This wire is specifically designed for carbon steel and has a specification that includes '70000psi - 6.'

What Does the Specification Mean?

The specification '70000psi - 6' on the ERS-70–6 wire provides important information about the wire's tensile strength and chemical composition.

Tensile Strength: '70000psi' indicates that the wire can withstand a tensile stress of 70,000 pounds per square inch before failure. This high strength is essential for welding steel with high tensile requirements. Chemical Composition: The '6' in the specification refers to the alloy composition, which typically includes a certain percentage of silicon and manganese. These elements help improve the weldability and mechanical properties of the steel.

Stainless Steel Filler Wire: 308Lsi

For stainless steel, 308Lsi wire is a popular choice. This filler wire is specifically designed for welding 304 stainless steel and can also be used to weld other types of stainless steel, such as 316 and 430.

Advantages of 308Lsi Wire

Low Carbon Content: The 'L' in 308Lsi stands for low carbon. Low carbon content helps reduce the formation of carbon inclusions in the weld, which can affect the strength and ductility of the metal. Low Sulfur Content: The 'Si' in 308Lsi indicates that sulfur, which can lead to hot cracking, is minimized in the wire. This makes the 308Lsi wire more suitable for welding applications where hot cracking is a concern.

Aluminum Filler Wire: 5356

When welding aluminum, the 5356 aluminum wire is commonly used. This wire is designed for its excellent weldability and minimal discoloration after welding, making it suitable for cosmetic applications.

Properties of 5356 Aluminum Wire

The 5356 aluminum wire has a unique combination of properties that make it ideal for MIG welding:

Fuseability: The wire has a low melting point compared to other aluminum alloys, making it easy to fuse during the welding process. Minimal Discoloration: After welding, the aluminum remains relatively clean and shiny, which is particularly important for cosmetic and aesthetic purposes. Tensile Strength: While not as high as carbon steel, the 5356 aluminum wire still offers sufficient tensile strength for many applications.

Conclusion

The choice of filler wire in MIG welding is critical to achieving a strong, durable, and reliable weld. The ERS-70–6 wire is ideal for carbon steel, the 308Lsi wire is suitable for stainless steel, and the 5356 aluminum wire is perfect for aluminum projects. Understanding the specifications and properties of these wires can significantly enhance the success of your welding projects.

Further Reading

In-depth Guide to MIG Welding for Carbon Steel Understanding Stainless Steel with 308Lsi Filler Wire How to Select the Right Aluminum Wire for MIG Welding