Metallizing is often used as an alternative to hot dip galvanizing and there are several advantages in choosing metallizing. The following is a list of some of those advantages:
- Appearance – The color and appearance of metallizing is uniform and continuous and does not leave puddles, laminations, uneven or marbled finish like often occurs with galvanizing.
- Mobility – Metallizing can be done anywhere the equipment can be taken. Galvanizing can only be done at the facility where the kettle is located.
- Sizes – Metallizing can be performed on any size structure. Galvanizing is strictly limited to what will fit in the kettle.
- Consistency – Metallizing results in a very uniform appearance as well as consistent performance in regard to adhesion. Galvanizing can vary greatly from batch to batch based on the kettle temperature, the time an object is submerged, and the strength of the bond. It is not uncommon to find galvanized areas exhibiting strong adhesion within inches of areas with bubbles and laminations.
- Existing Structures – Metallizing can be performed on any steel structure once the existing coating is removed. In order to be galvanized, a structure would have to be disassembled and shipped to a galvanizing facility, which can be extremely expensive.
- Top Coating – Metallized objects can easily be coated with a paint system to meet color codes or to provide an architecturally desirable color. A metallized surface is porous enough that paint is readily accepted into the surface profile and adheres as well as it would to a blasted substrate. Galvanizing is very difficult to topcoat with a paint system. In fact, many facilities refuse to apply paint over a galvanized item due to the poor finish appearance and notoriously inconsistent adhesion and intercoat bubbling that can occur.
- No Paint Areas – Often times structures have areas that do not get painted due to their surfaces being slip critical or having a machined finish. These areas are easily preserved when metallizing simply by masking them off and avoiding the surface. This is not possible when galvanizing due to the fact that the whole structure must be submerged in the kettle. These areas would have to be ground off or worse, machined again.
- Multiple Alloy Options – Metallizing wires range from the standard zinc, zinc/aluminum and aluminum, to the more unique such as tungsten carbide, bronze, aluminum bronze, copper, NiMoCr (Nickel Molybdenum Chromium), and even ceramic composites. Galvanizing is limited to zinc. This is notable because there are many atmospheric conditions where zinc is not as effective as a corrosion inhibitor compared to aluminum and other available alloys.
- Industry Standards – Metallizing is subject to the strictest of testing as laid out in the Joint Standard of the Society of Protective Coatings (SSPC), the American Welding Society (AWS) and the National Association of Corrosion Engineers (NACE) titled SSPC CS.23/AWS C2.23M/NACE No.12. It defines the surface preparation, application and testing of metallized coatings and requires us to perform a series of tests including bend testing for applicators as well as chisel and pneumatic adhesion tests of the finished product. This results in consistent outcomes for appearance and performance. Galvanizing is only subject to ASTM A 123 which simply states that the finish should be continuous, smooth and uniform. These terms are vague and subjective and this can become evident a galvanized product, particularly from piece to piece.
These are just a few of the reasons to consider utilizing a metallized coating on your next corrosion control project. For more information on metallizing, please visit the metallizing section of this website, or direct message us, or call us at 724-379-6440.