How to Ensure Your Project’s Powder Coating Lasts for Years

Powder coating is a modern finishing process where a dry powder made of resin and pigments is electrostatically sprayed onto a metal surface, then cured under heat. Unlike traditional liquid paint, powder coating produces a smooth, durable, and environmentally friendly finish that resists scratches, corrosion, and fading. It is widely used in industries such as construction, automotive, furniture, and metal fabrication for its high performance and attractive appearance.

Powder coating has been widely used in various products because people value not only durability but also the availability of vibrant colors and finishes. From household appliances and automotive parts to architectural structures and outdoor furniture, powder coating provides both protection and visual appeal. Its ability to deliver glossy, matte, or textured effects makes it a preferred choice for designers and manufacturers who want long-lasting performance with attractive aesthetics.

Let’s explore how powder coating works and what quality factors you should consider to ensure it is the right finishing choice for your project. By understanding the process, common issues, and inspection standards, you can make sure your coated products deliver both long-lasting protection and the appearance you expect.

Powder Coating Process Flowchart

1. Surface Preparation

• Incoming Material Check → Remove oil/grease (degreasing)

• Abrasive Blasting / Sanding → Achieve correct profile

• Chemical Pretreatment (Phosphate/Zirconium/Chromate)

• Rinse → Dry Completely

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2. Powder Application

• Inspect Clean Surface

• Check Grounding (<1 MΩ)

• Electrostatic Spray Gun Setup (60–100 kV, correct distance)

• Apply Powder → Ensure full coverage, no bare spots

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3. Curing

• Load into Oven

• Monitor Metal Temperature (probes/data loggers)

• Follow Supplier Cure Schedule (e.g., 180 °C × 15 min)

• Cool Down → Handle Carefully

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4. Quality Inspection

• Film Thickness Check (60–120 µm typical)

• Visual Check (no runs, pinholes, orange peel, color match ΔE ≤ 2)

• Adhesion Test (Cross-hatch ISO 2409 / ASTM D3359)

• Gloss & Hardness Test (if required)
  
  
   

1. Poor Adhesion / Peeling

Causes:

• Inadequate surface prep (oil, grease, rust not removed).

• No or improper chemical pretreatment.

• Contaminated substrate (silicone, fingerprints).

2. Orange Peel Texture

• Causes:

• Too high film thickness.

• Improper curing (too low temp or too short).

• Powder flow properties not suited to application.

3. Pinholes / Bubbles

• Causes:

• Trapped air or moisture in substrate.

• Outgassing from porous metals (castings, hot-dip galvanized steel).

• Excessive film thickness.

4. Cracking / Flaking after Curing

Causes:

• Excessive film build (>150 µm).

• Poor flexibility of powder type (hard epoxy used on flexible substrates).

• Sharp edges not rounded (weak adhesion).

5. Contamination (Dust, Fibers, Inclusions)

Causes:

•       Poor housekeeping in booth/oven area.

• Air supply contaminated with oil or water.

• Operator clothing shedding fibers.

6. Corrosion Under Film (Blistering, Rust)

Causes:

•       Inadequate pretreatment (no phosphating/zirconium).

• Edge coverage too thin.

• Mechanical damage exposing bare steel

Powder coating is one of the most reliable and versatile finishing methods available today, but like any process, it can face challenges such as poor adhesion, orange peel, or pinholes if not properly managed. By paying attention to surface preparation, correct application techniques, and curing standards, most of these common issues can be prevented. For customers, the key to a successful project is choosing a trusted partner who follows strict quality control and industry standards. When done right, powder coating not only enhances the appearance of your products but also ensures long-lasting durability, making it a smart investment for any project.

Looking for powder coat service? 
Get quote from:
joyce.tan@pvemetal.com.sg