Reliability. Environmental. Collaboration.
MacDermid Enthone Aerospace & Defense coatings include are known for their reliability, unsurpassed corrosion protection and wear resistance. Our environmentally (REACH and RoHS) compliant processes are OEM approved and backed by global alliances. Examples include:
- Aluminum conversion coatings to protect and aid paint adhesion for the fuselage
- Electroless nickel provides protection and wear resistance to engine components
- Hard chromium electroplating to provide wear resistance for landing gear
- Surface preparation to prepare the base metals for subsequent coatings
- Zinc-nickel electroplating to provide sacrificial corrosion protection for fasteners
Technology Overview
Aluminum conversion coatings
Iridite NCP, EXP and 14-2 provide excellent corrosion resistance to the aluminum alloy. These coatings can be applied as the final finish or as a primer to improve paint adhesion. Typical applications could include interior and exterior surfaces of an airplane body and mechanical components used in landing gear.
Where magnesium is used, Iridite 15 is the recommended conversion coating.
These products are specified by companies such as AMS, American Airlines, Boeing, General Dynamics, McDonnell Douglas and Pratt & Whitney.
Surface preparation
Removing oil, grease and general soils from metals such as aluminum, brass, magnesium and steel is a critical step in any surface treatment process. The MacDermid Enthone range of Clepo, ENPREP, Isoprep and Metex cleaners are proven to provide a chemically clean surface in the demanding conversion coating, electroplating and pre-paint applications. The range includes:
- Non-etch cleaners for light metals
- Etches for aluminum
- Soak degreasers for ferrous and non-ferrous metals
- Electrolytic cleaners for ferrous and non-ferrous metals
These products are extensively specified by the leading aerospace organizations.
Acid Activation and Alkaline Derusting
Dry acid salts ACTANE 32, Metex M629 and Alkaline deruster Isoprep 177 are used to remove oxide and activate steel surfaces. The advantages of these products compared to mineral acids are they significantly reduce the potential to induce hydrogen embrittlement into the steel substrate. Typical applications would be as part of the pre-treatment cycle prior to hardchrome and zinc-nickel electroplating. This is recognized by Boeing and McDonnell Douglas.
Electroless Nickel
These deposits may contain up to 13% Phosphorus by weight and unlike normal electroplating processes, they are produced without any externally applied electric current. The coatings are applied to a wide variety of substrates with both simple and complex geometries. electroless nickel improves characteristics such as appearance, corrosion / wear resistance and magnetic properties.
Our electroless nickel systems are specified by companies such as AMS, American Airlines, Boeing, McDonnell Douglas, Pratt & Whitney and Westinghouse.
Zinc-nickel electroplating
The preferred alloy composition for Zinc-nickel electroplating is 12 – 15% nickel. This alloy gives exceptional sacrificial corrosion resistance and the coating is compatible with light metals such as aluminum and magnesium. Zinc-nickel is typically plated from an alkaline electrolyte to provide excellent alloy and deposit distribution.
Enviralloy Ni 12-15 is approved by Airbus and Enviralloy NiFlex 12 and meets MIL standard 39888 .
Passivation / Chromate Coatings
MacDermid passivation systems comprise the complete range of hexavalent chromium-free and chromate-based conversion coatings. They meet all existing zinc and zinc alloy passivation requirements. Today, the market makes particular use of the high performance, thermal shock resistant TriPass ELV passivates. These form an important layer in the ZinKlad hexavalent chromium-free coatings processes.
