HDPE Coated Aluminum Coil and Sheet

What is HDPE Coated Aluminum?

HDPE Coated Aluminum, namely High-Density Polyethylene (HDPE) Coated Aluminum, is a composite material formed by covering the surface of an aluminum substrate with a layer of HDPE film or coating through specific processes.

Its core composition is "aluminum + HDPE coating". It combines the high strength, electrical conductivity, and thermal conductivity of aluminum with the corrosion resistance, weather resistance, and insulation of HDPE, ultimately forming a functional "metal substrate + polymer protective layer" material. It is widely used in scenarios that require multiple material properties.

Structure

HDPE coated aluminum typically adopts the following configurations:

Double-layer coating: HDPE coating + epoxy resin
Triple-layer coating: HDPE coating + primer layer (adhesive layer) + epoxy resin
Single-layer coating: Pure HDPE coating

Structure

Characteristics

Mechanical strength: High rigidity and impact resistance.
Chemical resistance: Excellent resistance to acids, alkalis, and salts.
Electrical insulation: Excellent dielectric properties.
Weather resistance: Good UV stability, suitable for long-term outdoor use.
Low-temperature performance: Maintains flexibility in cold environments.
Environmental friendliness: Non-toxic and recyclable.

Customizable Specifications

Alloy: 1060, 3003, 3004, 3005, 3105, 5005, 5052, etc.
Temper: H12, H14, H16, H18, H22, H24, H26, H42, H44, etc.
Thickness: 0.1 mm – 6.0 mm (coil) or customized
Shape/Form: Coil, Sheet, Strip
Width: 30 mm – 2,200 mm
Primer thickness: 5–10 μm
Coating thickness: 20–50 μm (minimum 23 μm for double-layer, minimum 30 μm for triple-layer)
Color: Black, white, blue, yellow, red, green, or customized (Pantone/RAL color standards)

Worthwill's HDPE Aluminum in factory

Production Process

Worthwill adopts advanced coating production lines for efficient manufacturing:

Pre-treatment: Degreasing, rinsing, and passivation to remove surface contaminants and enhance adhesion.
Coating:
- Primer application: Roller coating and curing.
- Topcoat application: Coating with a high-density polyethylene (HDPE) layer and curing at 200°C – 300°C.
Curing: Oven curing to ensure complete polymerization of the coating.
Post-treatment: Slitting, embossing, film lamination, etc., as required.

Production Workflow

Quality Control

Test Item	National Standard Requirement (GB/T 17748-2016)	Actual Test Result	Result Judgment
Color Difference	ΔE ≤ 2.0	ΔE ≤ 1.0	Better Than Standard
Gloss Difference	≤ 10	≤ 5	Better Than Standard
Coating Thickness	Double-layer: Minimum 23 μm; Triple-layer: Minimum 30 μm	Double-layer: ≥ 25 μm; Triple-layer: ≥ 34 μm	Better Than Standard
Pencil Hardness	≥ HB	HB	Meets Standard
T-Bend	≤ 2T	≤ 2T	Meets Standard
Coating Adhesion	Grade 0	Grade 0	Meets Standard
Impact Resistance	≥ 50 kg	≥ 50 kg	Meets Standard
Water Resistance	No abnormality for 2 hours	No abnormality for 4 hours	Better Than Standard
Solvent Resistance	≥ 200 cycles (no coating abnormality)	≥ 500 cycles (no coating abnormality)	Better Than Standard
Acid Resistance (5% HCl)	No abnormality for 24 hours	No abnormality for 24 hours	Meets Standard
Alkali Resistance (5% NaOH)	No discoloration for 24 hours, ΔE ≤ 2.0	No discoloration or abnormality for 24 hours	Meets Standard
Nitric Acid Resistance	ΔE ≤ 5.0	ΔE ≤ 5.0	Meets Standard
Oil Resistance	No abnormality for 20 hours	No abnormality for 20 hours	Meets Standard
Salt Spray Resistance	4,000 hours, corrosion grade ≤ Grade 1	No corrosion or abnormality for 4,000 hours	Better Than Standard
Abrasion Resistance	≥ 5 L/μm	≥ 5 L/μm	Meets Standard
Stain Resistance	≤ 5%	5%	Meets Standard
Color Retention (4,000h)	ΔE ≤ 4.0 after 4,000 hours	ΔE ≤ 3.0 after 4,000 hours	Better Than Standard
Gloss Retention (4,000h)	Gloss reduction grade ≤ Grade 2 after 4,000 hours	Gloss reduction grade ≤ Grade 2 after 4,000 hours	Meets Standard

HDPE Coating vs. PVDF Coating

There are significant differences between HDPE coating and PVDF coating. Compared with PVDF coating, HDPE coating offers better cost-effectiveness, but its overall performance (such as weather resistance, corrosion resistance, and high-temperature resistance) is inferior to that of PVDF coated aluminum.

Comparison Dimension	HDPE Coating	PVDF Coating
Weather Resistance	10–15 years, prone to fading and chalking	More than 20 years, aging-resistant and non-fading
Corrosion Resistance	Resistant to weak acids/alkalis, not to strong solvents	Resistant to strong acids, alkalis, and strong solvents
High-Temperature Resistance	≤ 80°C (softens above 120°C)	≤ 150°C (short-term resistance to 200°C)
Hardness/Abrasion Resistance	Shore D 50–60, prone to scratching	Shore D 70–80, strong scratch resistance
Adhesion	Cross-Cut Test ≥ 4B	Cross-Cut Test Grade 5B, resistant to thermal cycling
Processing & Cost	Simple process, low cost (1/3–1/2 of that of PVDF)	Complex process, high cost
Appearance Stability	Prone to gloss loss in the long term	Excellent color and gloss retention
Environmental Friendliness & Food Contact	Recyclable, suitable for food contact	Recyclable, may release trace fluorides when burned

Application Fields

Construction Industry: Exterior wall/roof panels (weather and rain resistant, reducing building load); indoor decoration for shopping malls/airports (environmentally friendly, aesthetic, and easy to clean).
Automotive Industry: Automotive body decorative parts (door/roof trim panels, lightweight to reduce fuel consumption, corrosion and scratch resistant).
Advertising Field: Outdoor billboards/road signs (long-lasting color without fading, UV-resistant and maintenance-free); commercial signs (moldable with high recognition).
Home Appliances/Civil Use: Washing machine casings/rice cooker inner pots (resistant to detergents/high temperatures, environmentally friendly and non-toxic); balcony railings/air conditioner covers (easy to install, suitable for home styles).

Why Choose Us?

Worthwill has multiple color coating production lines, including:

4 two-coat two-bake production lines,
2 three-coat three-bake production lines,
More than 300 sets of auxiliary automated equipment.

This allows us to select the optimal production line based on your specific needs.

By choosing Worthwill's HDPE coated aluminum, you will benefit from faster delivery speed, more competitive prices, and excellent quality that meets the needs of various industries.