In daily life, aluminum bottle caps are widely used in the packaging of alcoholic beverages, soft drinks, bottled pharmaceuticals, and cosmetics. Among many materials, hot-rolled 3105 aluminum sheet has become an ideal choice for bottle cap production thanks to its excellent deep-drawing ability, corrosion resistance, and medium strength, ensuring product quality, safety, and aesthetic appearance.

Characteristics of 3105 Aluminum Alloy

3105 aluminum belongs to the Al-Mn alloy series. Its primary component is aluminum, with small amounts of manganese, magnesium, and other elements added. This provides the alloy with good anti-rust performance and moderate strength. Compared with pure aluminum, 3105 aluminum alloy maintains excellent ductility and formability, while offering better corrosion resistance and surface coating properties. These qualities make it particularly suitable for bottle cap manufacturing processes such as deep drawing and stamping.

Why Choose Hot-Rolled 3105 Aluminum Sheet?

Although 3105 aluminum can be produced by both cold rolling and hot rolling, the bottle cap industry prefers hot-rolled 3105 aluminum sheet for the following reasons:

• Uniform Structure: Hot rolling improves the internal structure of the aluminum sheet, reduces segregation and inclusions, and enhances mechanical properties.

• Superior Processability: Hot-rolled sheets are less prone to cracking during stamping and stretching, ensuring complete cap formation.

• Excellent Surface Quality: Hot-rolled aluminum offers smoothness and flatness, which facilitates printing, coating, or anodizing processes.

• Suitable for Mass Production: Hot rolling provides stability and efficiency, meeting the high batch consistency required in the bottle cap industry.

Why is 3105 Aluminum the Right Choice for Bottle Caps?

1. Good Anti-Rust and Corrosion Resistance: Protects against humid environments and certain chemicals, meeting essential packaging requirements.

2. Outstanding Deep-Drawing Performance: Its ability to withstand complex stamping without cracks or wrinkles makes it ideal for automated, high-speed bottle cap manufacturing.

3. Adequate Strength and Elongation: Ensures mechanical reliability during processing and final use.

4. Excellent Formability and Weldability: Easy to process for different cap designs.

5. Flat Shape and Clean Surface: Hot-rolled 3105 aluminum has no roll marks or oil stains, making it highly suitable for high-quality printing on bottle caps.

6. Food Safety: Complies with food-contact safety standards, is recyclable, and supports environmental sustainability.

Common Tempers and Thickness Specifications

Bottle-cap 3105 hot-rolled aluminum sheets are commonly supplied in the following tempers:

H14, H16, H18: For applications requiring higher strength and good stamping performance.

O temper: Soft and highly ductile, suitable for deep drawing or irregularly shaped bottle caps.

Typical thickness range: 0.15 mm – 0.5 mm
Width range: 200 mm – 1600 mm, customizable to customer needs.

• Applications of 3105 Bottle Cap Aluminum Sheet

• Wine Bottle Caps: Widely used for wine, spirits, and beer closures. Its deep-drawing ability allows for complex decorative and tamper-evident designs.

• Beverage Bottle Caps: Suitable for carbonated drinks, juices, and mineral water bottles, providing reliable sealing performance.

• Pharmaceutical and Cosmetic Caps: In the pharma and cosmetics industry, 3105 aluminum is favored for its cleanliness and corrosion resistance, ensuring high-quality closure solutions.

Other Aluminum Alloys for Bottle Caps

In addition to 3105, other aluminum alloys are also used in bottle cap production:

• 8011 Aluminum Foil: Commonly used for anti-theft closures, especially for liquor, wine, and PP/ROPP caps. It features excellent deep-drawing and anodizing properties.

• 1060 Aluminum Sheet: As industrial pure aluminum (Al ≥ 99.6%), it is suitable for stamping processes and often used in aluminum-plastic composite caps, widely applied in cosmetics and pharmaceuticals.