Metal Spray/Thermal Spray/Spray Galvanizing refers to the same process which has been in existence since the early 1900’s and is, to this day – a process used worldwide. The Metal Spray process involves the melting of a wire and using compressed air to project it onto the work piece. Coatings can be tailored to suit the environment into which the component will be located (Zinc is used in the process of Galvanising). Metal Spray is however not limited to Zinc coatings, the Metal Spray process can also use, but is not limited to – Aluminium, Copper, Steel and Bronze coatings. Particular materials perform better in certain environments and the Metal Spray process provides flexibility to ensure that the appropriate material is being used for the job.
Metal Spray is a process used all over the world, where molten metal or softened particles are applied to a prepared surface (substrate) to enhance its properties (hardness, anti-corrosion, wear, dielectric, restoring dimensions etc.). No solvents or chemicals are used, just pure metal.
How Does Metal Spraying Compare with Galvanising?
- No cure time meaning components and structures are ready for use immediately after application.
- Equipment is transportable meaning components can be coated on site – no transport or waiting issues.
- There is no limit to the size of component to be coated, unlike galvanising where it is only suitable for objects that fit in a zinc bath.
- Low heat input during spraying eliminates the risk of component distortion.
- The Metal Spray coating is porous and therefore the perfect surface to accept paint or powdercoat (duplex coatings) if required.
- No need to pre–etch etc.
- Low heat input eliminates the risk of thermal metallurgical degradation.
The above video will help to emphasise this low heat input by showing examples
that would lose definition, distort, warp or even melt when subjected to a high temperature.
- Sealed hollow fabrications may be treated without risk of explosion.
- In the rare instance that the Metal Sprayed Zinc coating was damaged, a chemical reaction (cathodic protection) prevents the product from rusting.
- There is no effluent disposal problem.
- Reduced stocks of zinc are required. Working capital is not tied up in a molten zinc bath.
- Fuel is not needed to keep zinc molten when the process is not in use.
- Metal spraying restores corrosion protection on damaged areas of welded galvanised steel (International Standards exist covering this).
- Coating thickness can be varied to provide extra protection in critical areas.
- The Metal Spray process is not limited to Zinc.
- Aluminium, Steels, Bronzes etc. can also be applied for a variety of applications.
- No re-work required from galvanising dross.
What Do I Need to Apply the Metal Spray?
Before applying the coating, the component requires the surface to be clean, dry and grit-blasted to a SA 2.5 standard with a profile of 50µ (this can vary depending on the material being applied and coating thickness). The coating is then applied with one of the many methods of application used with the Metal Spray process.
Our range of Metal Spray equipment consists of Arc Spray, Flame Spray, Plasma Spray, High Velocity Air-Fuel (HVAF), High Velocity Oxygen-Fuel (HVOF) and Laser Cladding equipment. More information on each process is available by clicking on the relevant tabs.
The process is predominantly used for anti-corrosion and rebuilding engineering dimensions and has been used in every conceivable industry including Aerospace, Automotive, Marine, Biomedical, Agriculture, Space Travel, Power Generation, Infrastructure, Mining and many more applications. Metal Spray/Spray Galvanising is a technology that applies a surface coating of actual metal to a surface for corrosion protection. A common misconception regarding anti-corrosive coatings is that they can only be completed with Zinc, when in fact Metal Spray can offer 4 variations of anti-corrosion coatings, all of which have their own identities: Zinc 99.99%, Zinc Aluminium 85/15 alloy, Aluminium 99.5%, and Aluminium Magnesium 5%.
Metal Spray is the ideal surface to receive any top-coating from painting to powder-coating.
Metal Spraying New Bridge Structure – Image Provided Courtesy of LUMEN.
New Zealand’s Transport Agency published “Protective Coatings for Steel Bridges” (2014), a guide for Bridge and Maintenance Engineers, stating that metal coatings on bridges can give up to 40 years of protection until first maintenance.
The video below explores the anti-corrosion industry as a whole to show what can be achieved with the Metal Spray Process.
For more information, details, samples, or a demonstration of the process, call us on 07 3823 1004, or email us through our Contact Form.