Arc Spray: What is it and How Does it Work?

What is Arc Spray?

By definition, arc spraying is a thermal spray process wherein molten droplets are sprayed onto a substrate to form an interlocking surface deposit. In arc spraying, two consumable wire electrodes are used to form the electric arc. The heat of the electric arc melts the metal of the wire electrodes, and the resulting molten droplets are sprayed onto the substrate by a gas jet immediately behind the arc zone. The arc spray process is often used to apply coatings of zinc, aluminum, or other metals onto metallic substrates. The deposited metal coatings provide corrosion resistance and wear resistance properties.

Arc Wire Spraying Applications

Compared with other common thermal spray techniques, arc spray coating is particularly cost-effective/ It is typically utilized for the high speed application of metals like stainless steel, aluminum, and brass. Arc spray also offers a range of adjustment for different coating textures. Application sectors for arc spraying include:

Energy Production

In the energy production industry, arc spray is used to apply corrosion-resistant coatings to pipelines, storage tanks, and other metal surfaces that are exposed to harsh outdoor and marine environments. Coatings applied by arc spraying can protect against corrosion from salt water, chemical attack, wear, and abrasion.

Roll Resurfacing

Arc spray can also be used to resurface rolls used in the paper, textile, and metals industries. By applying a hard, wear-resistant coating to the surface of a roll, arc spray can extend its service life and improve its performance.

Advantages of Arc Spray

Can be used on a variety of metals

The arc spray process can be used to apply coatings of zinc, aluminum, stainless steel, and other metals onto most metallic substrates. Virtually any metallic material that can be drawn into wire form can be sprayed by arc wire spraying. Most commercially available MIG welding wires are compatible with arc spraying equipment. Certain specialty coatings can be created by running two wires of differing chemistry. This creates a spray deposit which is essentially a blend of the characteristics of both.

Rapid deposition

Arc spraying has deposition rates that far exceed most other conventional spraying methods. For this reason, arc spraying is advantageous for coating large surface areas and/or applying very thick coatings.

Economical operation

Most arc spraying requires only electricity and compressed air, making it simpler to apply in the field and less costly and complex, in terms of utility requirements and logistics. Arc spraying is often the preferred technique for field-applied coatings.

How Does Arc Spray Work?

The arc spraying process uses an electric arc to heat and melt the coating material. Two feedstock wires are electrically connected to the opposite poles of a high-current power supply. As the two conducting wires come into contact, an electric arc is struck that melts the wire and breaks the connection. Motorized pinch rollers advance the wire forward re-striking the arc, and spraying is sustained. The molten material is projected forward using a compressed gas jet located immediately behind the arc zone. The shower of molten droplets impact the target surface, where it instantly solidifies and forms a dense, adherent coating. Spraying can optionally be performed using an inert gas such as argon or nitrogen, instead of compressed air, to reduce the formation of oxides in the coating and create a cleaner deposit.

Flexible Quality Surface Treatment

Arc wire offers a portable and simple option for thermal spray applications. By bringing MIG welding technology to the field of thermal spray, arc wire makes it possible to apply a quality surface treatment at virtually any location. With its ability to provide an even coating and high deposition rates, arc wire is quickly becoming a popular choice for thermal spray applications.

Arc Wire Thermal Spray Experts

If you need arc wire for your next thermal spray application, look no further than Hayden Corp. Our solutions-based expert team of craftsmen and technicians will work with you to find the best solutions that affect your parts. Contact Hayden Corp. today to schedule a free consultation.