1. Process Flow

Pre-treatment (thin-film pre-treatment) → Powder primer coating → Curing → Intermediate coat / Topcoat

2. Advantages

a. Environmental Protection & Compliance

• Zero VOCs, no wastewater: Powder coatings are 100% high-solid with near-zero VOC emissions

• Powder recovery rate above 98%: Overspray powder can be recycled and reused, far superior to e-coating waste liquid treatment

• Meets stricter environmental and carbon reduction requirements for both domestic and export markets

b. Corrosion Resistance & Mechanical Performance

• Salt spray resistance: High-quality epoxy powder can achieve 800–1200 hours, close to e-coating levels

• Single coating thickness of 60–100 μm: Better impact resistance, stone-chip resistance, wear resistance, and chemical resistance than e-coating

• Outdoor weather-resistant powders can be used directly as topcoats, simplifying the coating system

c. Cost & Efficiency

• Eliminates e-coating tanks, ultrafiltration systems, rectifiers, and wastewater treatment equipment and maintenance

• Up to 98% coating efficiency, shorter process flow, lower equipment investment, reduced energy consumption, and material savings

• Lower life cycle cost (LCC), especially suitable for export scenarios requiring high corrosion resistance

Trucks: SMC Composite Parts — What Are the Advantages of Powder Coating?

A well-known domestic truck manufacturer has successfully implemented powder coating for SMC composite parts, meeting stringent outdoor weatherability and mechanical performance requirements in harsh environments. It effectively solves the following issues:

1. SMC composites have porosity that cannot be fully covered by liquid paint, leaving surface defects even after multiple coating layers

2. Mold release agents on the substrate surface cause adhesion failure, making it difficult to pass high-pressure water wash tests

Powder coating for SMC composites does not require special substrate treatment. After cleaning and drying, coating can be applied with excellent adhesion, meeting performance requirements such as high-pressure water resistance, moisture and heat resistance, environmental cycling, wear resistance, scratch resistance, stone-chip resistance, and chemical resistance—suitable for demanding conditions.

Key Advantages

• Higher yield rate: One powder coating layer replaces 2–3 layers of liquid paint, simplifying the process and significantly improving first-pass yield

• Strong adhesion: Powder forms a strong interface bond with composite materials, far superior to liquid coatings, and passes high-performance high-pressure water wash adhesion tests

• Excellent weatherability: Outstanding resistance to xenon lamp aging and superior coating protection performance

• Low VOCs: Powder coatings produce almost no VOC emissions, significantly reducing pollution and carbon output