Welding wires, or electrodes, are used as a filler for welding joints.
Welding wires, or welding electrodes, are used to sustain the welding arc flame and provide a filler metal for weld joints. They can be classified by metal content type, tensile strength, welding positions they can be used in, type of coating and the power supply you need to work with them. The most widely used classification system used in the United States is the American Welding Society, or AWS, classification, which uses an alphanumeric system to describe the characteristics of each welding wire type.
AWS A5.20 - Mild Steel
AWS A5.20 is the classification used for mild steel flux-cored electrodes. These electrodes can be used in any position and produce a soft arc with low spatter levels. This type of welding wire is used widely on pipelines, bridges, boilers and building construction. You can classify AWS A5.20 electrodes further by their tensile strength. For instance, the subcategory code E80T, tells you it is an electrode with a tensile strength of 80,000 pounds per square inch.
AWS A5.29 - Low Alloy
AWS A5.29 welding wires are made with low-alloy concentrations which provide high tensile strength, corrosion resistance, and longevity to your welding joints. You can match your AWS A5.29 electrode to the type of steel you are welding. Each weld wire type is classified by the chemical composition of the electrode. For example, a AWS A5.29 welding wire with the classification EXXX-B2 has 1.50 percent of chrome and 50 percent of molybdenum, while a EXXX-B8 has 8 to 10.50 percent of chrome and 50 percent of molybdenum.
AWS A5.4 - Stainless Steel
Stainless steel welding electrodes have the AWS code A5.4. They provide radiographic-quality welds and can be used in any welding position. Industry applications for stainless steel welding wires include the paper and textile industry, chemical mixers and the paints and dye industry.
AWS MIG Aluminum Alloys
Aluminum-to-steel welds require AWS MIG Aluminum welding wires. The two main types are ER-4043 and ER-5356. The 5356 is especially recommended for stronger welds and provides easier feeding. For best results with aluminum welding use a spool gun. Spool guns give you a more reliable and precise weld because the wire is directly connected to the welding gun.
