Fabricated Core Wires

Metal-cored wires and gas-shielded flux-cored wires can be formulated to give a suitable combination of mechanical properties, weldability, and productivity.  Due to the fact that these wires are fabricated they are very versatile and can be applied to many different applications.

• Suitable applications for flux-cored and metal-cored electrodes
• Gas-shielded flux-cored and metal-cored wires are growing in popularity because the wires are fabricated and can be applied to many applications.
• Gas-shielded flux-cored arc welding (FCAW) and metal-cored arc welding (MCAW) are growing in popularity for many applications.
• To determine if these wires should be used, shop managers should understand how formulations of cored wires do or do not fit their quality requirements for certain applications.
• All-position versatility is one of the greatest benefits offered by flux-cored wires. Over the years, developments in the flux-cored wire process have allowed these wires to be used for welding in all positions (including vertical and overhead) while maintaining the good mechanical properties and high productivity allowed by the high deposition rates in all positions.
• All-position flux-cored wires include arc stabilizers and slag systems that are formulated to support the weld pools, resulting in fast-freezing slag.
• The conducting part of cored wires is small, which results in high current density and helps to improve their net deposition rates.

• Because flux-cored wires have a slag covering the weld, post-weld removal of the slag is necessary. However, the slag generally is easy to remove and, in some cases, almost self-releasing.

• Flux- and metal-cored wires are particularly suitable for one-sided welding on open butt joints.
• Open butt joint welding requires a high skill level to achieve sufficient penetration with back-bead reinforcement and burn-through prevention.
• With cored wires and ceramic backing, however, the welder can choose a wire and match it with backing materials selected for optimum results in all welding positions while maintaining a high productivity level.
• Cored wires typically generate more fumes than other continuous welding processes because the cored wires deposit more weld metal per minute.
• In recent years, manufacturers have introduced cored wires that produce less welding fume and spatter.
• Cored wires have been formulated for use with high-argon gas mixtures previously used only for solid-wire GMAW. This use of special low-fume cored wires with a deposition chemistry balance for the use of higher-argon shielding gas mixtures tends to lower the fume and spatter levels commonly associated with flux-cored wires.
• Through a thorough understanding of MCAW and FCAW, welders doing various types of welding have been able to identify niches in which cored wires can contribute to higher productivity and quality improvements.
• The differences in flux formulations among different cored-wire products permit flexibility in meeting specific performance needs and end-result requirements.
• Not all applications are suitable for cored wires, but end users should be aware of the basic economics of welding to determine the actual cost per pound of deposited weld metal (rather than cost per pound of product) to choose the best wire for a particular application.

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