What are radiator cores made of?
Most modern passenger-car radiator cores are made from aluminum, which offers a light weight and strong heat transfer. Copper-brass cores are still found in some older vehicles and specialty radiators.
Radiator cores are the central heat-exchanging element of a cooling system, consisting of networks of tubes and fins through which coolant flows and air passes. The material chosen for the core affects weight, durability, corrosion resistance, and thermal performance, shaping design choices across vehicles and industries.
Core materials used in radiators
Various metals have been used historically and in modern designs. The following list highlights the most common core materials.
- Aluminum cores: The dominant choice in new cars and light trucks due to low weight, good thermal conductivity, and cost-effective manufacturing. Tubes and fins are typically extruded or formed from aluminum alloys and bonded to end tanks (often plastic).
- Copper-brass cores: Historically widespread and prized for superior thermal conductivity, but heavier and more expensive. Still found in some vintage vehicles and certain high-performance or specialty radiators.
- Other materials: In some industrial or specialized applications you may encounter stainless steel or composite materials, but these are rare for standard automotive cores. Some high-end or racing radiators may use alternative alloys or reinforced fins for specific cooling needs.
In practice, automotive manufacturers almost exclusively use aluminum for the core in modern production, with copper-brass reserved for legacy, restoration, or specialty builds.
Why material choice matters
Several design factors drive the choice of core material.
- Weight and fuel economy considerations
- Thermal performance and cooling capacity
- Corrosion resistance and coolant compatibility
- Manufacturing cost and supply chain considerations
- Durability, repairability, and service life
Thus, while the core always includes tubes and fins, the surrounding context—vehicle type, operating environment, and cost—determines whether aluminum or copper-brass is used.
Historical and modern trends
In the mid-to-late 20th century, copper-brass radiators were standard in many vehicles due to their excellent thermal properties and manufacturability. As automotive engineering advanced and regulations demanded lighter vehicles with better efficiency, manufacturers shifted to aluminum cores in most mass-market models. Electric vehicles and high-performance applications continue to push for optimized heat exchangers with advanced materials, but aluminum remains the baseline for cores in most current designs.
Summary
Radiator cores are primarily made of aluminum in today’s vehicles, offering a favorable balance of weight, heat transfer, and cost. Copper-brass cores persist in legacy, restoration, or specialty radiators due to higher thermal conductivity but come with greater weight and expense. The best material choice depends on the application, emphasizing efficiency, durability, and practicality for the vehicle or system in question.
