Aluminum Brazing Sheet Coil

Aluminum Brazing Sheet Coil is a composite structural material consisting of an aluminum alloy core (such as 3003, 3105) and a cladding layer of low-melting-point brazing alloy (such as 4343, 4045, 7072). Specifically designed for thermal management systems, it enables efficient low-temperature brazing in vacuum or protective atmosphere environments, widely used in thermal management applications such as battery cooling plates for new energy vehicles, automotive heat exchangers, HVAC modules, and industrial waste heat recovery systems.Contact Us

Chalco can provide the following main rolled product specifications:

Want to precisely match the brazing alloy? One-click access to the selection guide

The requirements for brazing alloy type, core material performance, and anti-corrosion layer design vary greatly depending on the product form. To help you select more efficiently, we have set up a complete brazing alloy selection guide at the bottom of the page.

Why Choose Chalco Brazing Aluminum Sheet Coil?

Compared with traditional aluminum sheets, brazing aluminum sheet coil has the following core advantages:

• Good Low-Temperature Solderability: Cladding layer melting point 577 - 600℃, compatible with vacuum/atmosphere brazing;
• Lightweight and High Thermal Conductivity: Density is only 1/3 of copper, thermal conductivity reaches 180 - 240 W/m·K;
• Composite Integrated Structure: Supports single-layer, double-layer, and three-layer composites (such as 7072/3003/4343);
• Good Processing Compatibility: Suitable for various processes such as stamping, bending, laser cutting, and coiling.

Aluminum Brazing Sheet

Brazing aluminum sheets are manufactured by roll bonding a core alloy (such as 3003, 3105, 6951) with a cladding layer of brazing alloy (such as 4343, 4045, 7072), providing excellent thermal conductivity, sealing performance, and corrosion resistance. Chalco can provide single-sided or double-sided clad structures as needed.

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Specifications

Thickness Range: 0.4 - 6.35 mm

Width Range: 500 - 1600 mm

Maximum Length: 6000 mm

Cladding Method: Single-sided / Double-sided / Three-layer composite

Cladding Rate: 5% / 7.5% / 10% / 13% / 15% (customizable)

Alloy Structure

Single Alloy Core: 3003, 3105, 6951

Cladding Alloy Structure: 4343/3003, 7072/3105/4343, 4045/6951

See alloy selection guide below for details.

Typical Applications

• Battery cooling base plates and module manifolds
• Manifold support surfaces in HVAC systems
• Structural modules for industrial high-temperature heat exchangers
• Brazed housings and plate components for air conditioning/automotive radiators

Designing a brazed structure? Chalco can assist with alloy matching, plate design, and welding compatibility verification, supporting simultaneous prototyping of multiple product categories. Welcome to contact us for technical support and sample quotations!Quick Quote

Aluminum Brazing Coil Strip

Brazing aluminum coils strips, made via precision slitting, suit automated forming, stamping, and coil brazing in heat exchangers, battery manifolds, and multi-channel structures. Chalco offers customizable thickness, cladding, width, and surface treatments.

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Specifications

Thickness Range: 0.05 - 3.0 mm

Width Range: 6 - 1600 mm

Temper: O, H14, H18, H24, etc.

Inner Diameter: 305mm, 405mm, 505mm (paper core, aluminum core, coreless)

Outer Diameter: ≤1600mm

Surface Treatment: Mill finish, anodized, electrophoretic coating, anti-corrosion film

Alloy Structure

• Single Alloy Coil / Strip: 3003, 3005, 3105
• Bi-layer Composite: 4343/3003, 4045/3003, 4045/6951
• Tri-layer Composite: 7072/3003/4343, 4343/3105/4343

See alloy selection guide below for details.

Advantages

• Adaptable to high-speed automated brazing lines with continuous coil feeding, saving processing time;
• Supports various composite structures (such as 7072/3003/4343), balancing corrosion resistance and brazing performance;
• High flatness and edge control, suitable for forming multi-channel or complex flow channel structures.

Typical Applications

• Connection strips for air conditioning condenser fins and main pipes
• Strip material for heat dissipation flow channels in electric vehicle battery modules
• Edge sealing strips for vacuum brazed cooling plate structures

Click the button below to contact us for technical support and sample recommendations.Get sample

Aluminum Fin Stock

Aluminum fin stock is a thin-gauge material designed for efficient heat exchangers, widely used in radiators, condensers, and battery cooling modules. Chalco offers high-strength, high-conductivity, brazeable fin stock with coil supply and corrosion-resistant coatings.

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Specifications

• Thickness: 0.07–0.50 mm
• Width: ≤1600 mm
• Form: Coil; supports large rolls and custom slitting
• Tempers: H14, H16, H18

Alloy Options

• Standard Alloys: 4004, 4104, 4047, 6951
• Clad Fin Alloys: 4343/3003/4343, 4045/3003/4045, 4047/3003/4047, 7072/3003/7072

See alloy selection guide below for details.

Key Advantages

• Excellent brazeability: Suitable for CAB and vacuum brazing
• High thermal conductivity: 180–240 W/m·K
• Good formability: High elongation, uniform fin height, low warping
• Coating support: Custom anti-corrosion, hydrophilic/hydrophobic coatings available

Typical Applications

• Radiator fins for passenger and commercial vehicles
• Multi-layer fins in HVAC condensers and evaporators
• Battery cooling fins in EV and energy storage systems
• Ultra-thin fins in industrial heat exchangers

For alloy selection, coating compatibility, and forming guidance, please contact the Chalco engineering team.Solution

Brazing Aluminum Alloy Selection Guide

When selecting an alloy system suitable for brazing aluminum sheet / coil, it is necessary to comprehensively consider the brazing process (vacuum / protective atmosphere), application environment (corrosion / pressure resistance / heat dissipation), structural strength, and cost control. The following is a reference for mainstream alloy selection summarized by Chalco based on actual project experience:

Homogeneous Core Alloy

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  Single alloy brazing aluminum sheet coil usually does not contain a brazing filler layer and is used as a structural support material. It can also be externally welded with other brazing filler foils. Its characteristics include good formability, high thermal conductivity, and low cost, making it suitable for applications with low brazing requirements but certain requirements for stamping, bending, and strength.Quick Quote

Product

Two-Layer Clad

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  Two-layer clad is the most common form of brazing aluminum material, with a brazing filler layer (such as 4343 or 4045) clad on one or both sides. During the brazing process, it melts upon heating to form a welded joint. The number of clad sides and the cladding rate can be adjusted according to usage needs, balancing strength, weldability, and cost control.Contact Us

Through the rolling composite process, a low-melting-point brazing filler layer (such as 4343, 4045) is clad on the surface of a core material (such as 3003, 6951) to achieve low-temperature brazing (575-600℃), widely used in high-efficiency heat exchange applications. Key advantages include high sealing performance, corrosion resistance, and lightweight properties.

Multi-layer & Special Brazing Materials

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  Brazing alloy clad on both sides (e.g., 4343/4045) is suitable for heat exchange components requiring brazing on both sides, ensuring uniform contact and stable welding. It is commonly used in medium to high-pressure scenarios demanding high sealing performance, such as evaporators and double-sided cold plates.Contact Us

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  Clad with brazing material on one side and a 7072 anti-corrosion layer on the other, this configuration offers self-protection capabilities and is suitable for highly corrosive environments such as coastal equipment, marine coolers, and battery systems, enhancing overall service life.Free Samples

Cladding Structure Technical Parameters

Cladding Method: Optional single-sided, double-sided;

Cladding Rate: Supports 5%, 7.5%, 10%, 13%, 15%, other cladding ratios can be customized;

Cladding Layer Tolerance:

• 1.5 - 4%:±0.6
• 4 - 6%:±1.0
• 6- 12%:±1.5
• 12 - 20%:±2.0

Whether you need lightweight and high thermal conductivity materials for battery cooling plates or seawater heat exchange module structures with anodic protection, Chalco can provide you with brazing aluminum alloys covering various composite methods, different strength grades, and corrosion resistance properties.

We support sample development, customized cladding structures, and brazing performance verification to help your thermal management projects achieve efficient implementation.Get Quote

Application Scenarios and Solutions

Brazing aluminum sheet/coil excels in mid-to-high-end thermal management due to its light weight, high thermal conductivity, brazeability, and corrosion resistance, meeting diverse heat exchange needs. Chalco offers customized material configurations and processing support based on project scenarios.

New Energy & Automotive Thermal Management

• Battery Water/Liquid Cooling Plates/Modules: 4343/3003 or 7072/3003/4343 (brazing + anodic anti-corrosion for high airtightness and long-term corrosion resistance).
• Oil/EGR Coolers: 4045/6951, 4343/3105 (high pressure/temperature, enhanced cooling).
• Intercooler/Evaporator Flat Tubes: 4045/3003, 4047/3003 (complex flow channels, vacuum brazing).

HVAC

• Condenser Fins/Manifolds: 4343/3003 double-sided clad (multi-stage brazing + fin integration).
• Microchannel Flat Tubes/Brazing Fin Stock: Ultra-thin 0.08-0.2mm fins (3003-H16) or three-layer fin strips (high heat exchange efficiency).
• Evaporator Modules/Duct Systems: 3105 or 3003 single alloy (structural strength and thermal conductivity).

Energy Storage & Battery Cooling

• Liquid Cooling Plates/Modules: 7072/3105/4343 (good corrosion resistance, weldability, strength).
• Manifolds/Heat Exchange Components: 4045/3005 or 4343/3105 (complex paths, precision brazing).
• High Airtightness Brazed Cooling Chambers: 4047/3003 (helium leak test compatible, vacuum brazing).

Industrial Heat Exchange

• Oil/Gas Recovery, Flue Gas Waste Heat: 4045/6951, 4343/6951 three-layer (high-temperature strength, corrosion resistance).
• Industrial Condensing Modules: Customized 0.6-2.5mm clad brazing aluminum (high structural stability, long-term continuous operation).
• Marine Heat Exchangers/Offshore Cooling: 7072/3003/4343 (salt spray ≥2000h, pitting corrosion life x2+).

Chalco supports comprehensive selection design, brazing compatibility verification, and sample provision.Get Application Guide

Why Choose Chalco for Your Brazing Aluminum Sheet / Coil Partner?

Chalco specializes in the R&D and production of brazing aluminum materials, possessing integrated manufacturing capabilities from composite rolling to customized slitting, enabling us to provide high-quality and competitive material support for global thermal management systems.

In-house Composite Rolling + Precision Slitting Capabilities

Our own composite strip production lines support efficient mass production of double-sided/three-layer clad brazing aluminum materials with precise control over thickness and cladding rate.

Customized Composite Alloy Structures

We can customize various composite systems such as 4343/3105 and 7072/3003/4343 to meet the combined requirements of strength, corrosion resistance, and brazing performance for different application scenarios.

Comprehensive Quality Certification System

Our products comply with international certifications such as ASTM, ISO 9001, and IATF 16949, and we support EN 10204 3.1 material reports and shipment quality guarantees.

Global Delivery, Flexible Trade Services

We support multi-mode export including FOB / CIF and can provide certificates of origin, chamber of commerce certification documents, and all customs-required information.

Frequently Asked Questions

1. Which material is most suitable for vacuum brazing?

We recommend using a single-sided clad structure of 4047/3003 (eutectic melting point 577℃), which offers good fluidity and minimal residue, especially suitable for fuel cell bipolar plates and semiconductor modules requiring high cleanliness. If strength is also a concern, you can upgrade to a double-sided clad structure of 4045/6951. It is recommended to use plasma cleaning to treat the surface before welding to improve joint quality.

2. What if brazing aluminum coils easily fail in high corrosion environments?

Ordinary 4343/3003 has a short lifespan in salt spray environments. We recommend a three-layer composite structure of 7072/3003/4343, where the 7072 Zn layer can provide anodic self-protection, with a salt spray life ≥2000 hours. If combined with anodic oxidation sealing treatment, it can be further extended to over 3000 hours.

3. What are the issues if the solder doesn't flow or there is significant warpage after welding?

Common causes include insufficient cladding rate (recommend ≥10%), insufficient core material strength (3105-H16 or 6951-T6 can be used), and unreasonable control of the brazing thermal cycle. Optimization solutions include using a symmetrical structure such as 4343/3105/4343 and controlling the heating rate within 10℃/min to reduce thermal stress.

4. Can brazing aluminum coils be directly stamped or bent? Will they crack?

They can be used for stamping/bending, but you need to choose tempers with good ductility such as 3003-H14 and 3105-H16. It is recommended that the die clearance be ≤10% of the material thickness and that edges be chamfered (R≥0.5mm) to prevent cracking. The interlayer bonding strength of Chalco's composite materials is ≥30N/mm, ensuring reliable stability.

5. Can you supply quickly? Do you support relevant certifications for export projects?

Chalco can deliver regular specification products within 7-10 days and provides a full set of certifications including ASTM, EN, IATF16949, RoHS, REACH, as well as EN 10204 3.1 material reports, certificates of origin, and third-party inspection reports to meet the compliance needs of the automotive, thermal management, and energy industries.Contact Us

6. How to reduce the cost of brazing aluminum coils while ensuring performance?

Cost expenditure can be effectively controlled by reducing the brazing filler cladding rate (e.g., using 5% instead of 10%), selecting recycled aluminum base core material (controlling impurities Fe≤0.25%), or performing wall thickness simulation optimization to reduce material usage.

7. Can brazing aluminum coils still be used stably under high temperature and high pressure?

We recommend using 4045/6951-T6 double-sided composite materials, with a temperature resistance of up to 300℃ and a short-term peak of up to 350℃, and a burst pressure ≥15MPa. Widely used in high-temperature heat exchange modules, automotive oil coolers, industrial waste heat recovery equipment, and other high-strength working conditions.

8. How to deal with discoloration or blackening of the surface after brazing?

The following options are available:

• Chemical polishing (HF+HNO₃) to improve surface finish.
• Micro-arc oxidation to enhance corrosion resistance and hardness.
• Epoxy spraying protection, suitable for outdoor/highly corrosive environments, with a weather resistance ≥10 years.

9. How to avoid discontinuous welds in complex brazed structures?

It is recommended to use pre-placed 4047 brazing filler foils to improve filling integrity, combined with laser-assisted heating to locate the melting zone. Graphite molds can be used for fixtures, offering good thermal expansion consistency and less welding deformation.

10. How to achieve dissimilar metal brazing of aluminum with copper or stainless steel?

The following methods can be used:

• Aluminum-copper transition layer: Nickel plating (2–5μm) followed by welding with Al-Si-Mg brazing filler.
• Connection with stainless steel: Select Ag-based brazing filler (such as BAg-8) and operate under inert gas protection.
• Non-welding scenarios: Use hydraulic expansion + structural adhesive solution, with a pressure resistance of up to 5MPa.

Want to obtain more detailed technical parameters or customized alloy recommendations? Click the button below to contact the Chalco engineering team for one-on-one selection services.