01 Mar How to Clean and Protect Powder Coated Materials
Proper cleaning, inspection, and documentation preserve powder-coated components, ensuring corrosion resistance, mil-spec compliance, and long-term aerospace performance.
By Hugo Canales
In aerospace and defense manufacturing, coating performance is directly tied to mission readiness and contract compliance. When a powder-coated component fails prematurely, the root cause is often improper cleaning, inadequate inspection, or preventable environmental exposure. At Royal Coatings, we apply NADCAP-accredited chemical processing and controlled application methods to ensure every finish performs to specification. Maintaining that performance requires disciplined handling and maintenance throughout the component’s lifecycle.
Understanding Powder Coating Performance in Aerospace and Defense
For aerospace and military hardware, powder coating provides optimal film thickness, strong electrostatic bonding, and excellent corrosion resistance. The process involves applying a charged powder to a grounded part, followed by controlled curing at an elevated temperature to form a resilient film.
These coatings are used on aircraft structures, military technology, and critical metal assemblies exposed to temperature swings, salt-laden air, hydraulic fluids, and UV radiation. While powder coatings are durable, they are not maintenance-free. Their long-term protection depends on proper surface preparation, careful cleaning, and a structured inspection program.
Proper Cleaning Without Damaging the Finish
Cleaning aerospace and military components requires discipline. Improper methods can compromise adhesion or degrade the protective barrier.
Approved Cleaning Methods
- Use mild, pH-neutral detergents diluted in warm water.
- Apply with non-abrasive cloths or soft-bristle brushes.
- Rinse thoroughly with clean water to remove residue.
- Dry with lint-free cloths or filtered compressed air.
Avoid aggressive scrubbing pads, metallic brushes, or abrasive compounds. Powder coatings achieve uniform coverage and edge protection through electrostatic deposition and curing, but mechanical abrasion can thin the film below specified tolerances.
Cleaning Agents to Avoid
Avoid the following unless explicitly authorized by engineering documentation:
- Strong solvents such as MEK or lacquer thinner
- Chlorinated cleaners
- Highly alkaline or acidic degreasers
- Abrasive polishing compounds
In military environments, coatings may be part of a broader protection system, such as CARC or mil-spec topcoats. Unauthorized chemicals can compromise chemical resistance and compliance with specifications such as MIL-DTL standards.
Surface Preparation and Its Long-Term Impact
Long-term protection begins before the first cleaning cycle. Surface preparation is foundational to coating adhesion and corrosion resistance.
All parts must be clean, grease-free, and free of foreign material before coating. At Royal Coatings, we operate a three-stage phosphate pre-treatment system and controlled preparation processes within our 20,000-square-foot facility. That preparation directly influences how well the coating withstands years of environmental exposure.
If a part was improperly prepared before coating, no maintenance program can fully compensate for it. Adhesion failures, underfilm corrosion, and blistering typically trace back to insufficient pre-treatment.
Risks of Pressure Washing and Solvent Cleaning
Pressure washing can be acceptable when controlled. Excessive PSI directed at edges, seams, or masked interfaces can force moisture beneath the film. Once moisture penetrates, corrosion can propagate beneath the coating.
Solvent cleaning presents a greater risk. Powder coatings are formulated to resist wear and corrosion, but repeated exposure to aggressive solvents can dull the surface or degrade protective properties. Always verify compatibility with the original coating specification before introducing any solvent-based maintenance practice.
Inspection Frequency in Harsh Environments
Aerospace and defense hardware routinely encounters:
- UV radiation at altitude
- Salt spray in marine or coastal deployments
- Hydraulic fluids and fuels
- Temperature extremes
Salt-exposure testing protocols, such as those defined by ASTM B117, provide a benchmark for evaluating corrosion resistance under controlled conditions. Field exposure can be more variable and more severe.
For components in coastal or chemical-heavy environments, I recommend visual inspections at least quarterly. For sheltered interior assemblies, semiannual inspection may be sufficient. Look for:
- Edge wear or thinning
- Impact damage
- Blistering or bubbling
- Discoloration or chalking
Early identification prevents widespread recoating or rejected assemblies.
Common Causes of Premature Failure
In my experience overseeing aerospace and military programs, most premature coating failures stem from preventable issues:
- Inadequate surface preparation before coating
- Unauthorized field touch-ups with liquid paint
- Mechanical abrasion during assembly
- Exposure to incompatible cleaning chemicals
- Poor documentation of coating batch or cure parameters
Powder coating eliminates common paint defects such as runs and sags, but it still requires controlled handling after application.
Environmental Factors That Degrade Coatings
Environmental stressors affect every finish over time. Aerospace coatings must protect against corrosion, resist wear, and ensure long-term performance.
Key degradation factors include:
- Prolonged UV exposure leads to a reduction in gloss.
- Salt-laden air is accelerating corrosion at damaged edges.
- Chemical exposure is weakening the film surface.
- Thermal cycling causes stress from expansion and contraction.
Understanding the deployment environment allows purchasing agents and planners to specify the correct powder formulation from the outset.
Repair Versus Full Recoating
Minor surface damage can sometimes be repaired using approved methods. However, unauthorized touch-up with standard wet paint is strongly discouraged. Mixing coating systems can create compatibility issues and may violate customer specifications.
If damage penetrates to bare metal or affects a mil-spec assembly, full stripping and recoating may be required to maintain compliance. For defense contracts, any repair decision should align with the governing specification and customer quality clauses.
Powder Coating Compared to Liquid Paint
Powder coating offers superior bonding, optimal thickness control, and stronger corrosion protection than traditional liquid paint. Liquid coatings rely on binders, solvents, and spray atomization to form a film.
In high-wear or corrosive environments, powder coatings generally reduce maintenance frequency. Liquid coatings remain essential for certain conductive, shielding, and CARC applications. The correct system depends on the end-use specification, not convenience.
Documentation and Quality Controls That Matter
For aerospace and defense subcontractors, documentation is as critical as performance.
Royal Coatings maintains NADCAP Chemical Processing Accreditation, reflecting disciplined process control, traceability, and compliance. Our Quality Management System governs preparation, application, curing, inspection, and final release.
Your coating partner should provide:
- Certification of conformance
- Cure logs and batch traceability
- Material certifications for QPL products
- Inspection reports verifying film thickness.
Without documented controls, even a visually acceptable coating may fail audit review.
When to Outsource Powder Coating
Smaller manufacturers often produce precision hardware but lack the enclosed booths, batch ovens, and mil-spec expertise required for aerospace work. Attempting to manage complex specifications internally can introduce rework, schedule delays, or rejected parts.
We routinely support subcontractors serving Boeing, Airbus, Raytheon, and other defense leaders. Outsourcing to a NADCAP-accredited partner reduces lifecycle cost by preventing failures before they occur.
Conclusion
Cleaning and protecting powder-coated aerospace and military components requires controlled methods, disciplined inspection, and strict adherence to specifications. When preparation, application, and maintenance are aligned, powder coatings deliver years of corrosion resistance and structural protection.
If your team is responsible for hardware that must pass inspection the first time, I encourage you to partner with a NADCAP-accredited provider. Review our full range of powder coating capabilities to ensure your next program meets performance requirements without compromise.
About the Author
As Vice President and General Manager of Royal Coatings, Hugo Canales brings over a decade of proven leadership in the powder coating, liquid coating, and advanced manufacturing industries. Hugo oversees a team of more than sixty skilled professionals, ensuring every project—from military and aerospace applications to medical and commercial equipment—meets the most demanding specifications for quality and precision.
With a background in City and Regional Planning from the University of California, Davis, Hugo combines strategic thinking with a deep technical understanding of industrial processes. Since joining Royal Coatings in 2017, he has guided our operations to consistently deliver MIL-SPEC coatings for major defense and aerospace contractors, including Raytheon, Lockheed Martin, Boeing, and Northrop Grumman.
Hugo’s leadership is grounded in a strong commitment to excellence, safety, and pride in artistry. His approach fosters a culture where every team member values craftsmanship, precision, and integrity in every finished surface. Under his direction, Royal Coatings continues to uphold its reputation as a trusted partner in the nation’s most critical manufacturing sectors.