Scientists have discovered a method to enhance the performance of 3D-printed aluminum bronze, a metal that could be useful for cooling high-powered electronic components in rockets, airplanes, and electric vehicles.
Researchers from Skoltech and the State Marine Technical University investigated how different heat treatments influence aluminum bronze produced through 3D printing.
They found that heating the printed metal to specific temperatures can create an improved balance between strength and flexibility—the capacity of a material to bend or stretch without breaking.
The results were published in the Journal of Alloys and Compounds.
Modern electronics generate significant amounts of heat, especially powerful processors and other high-demand components.
Heat exchangers help transfer this heat away, preventing overheating of sensitive electronics.
The material used for these cooling systems must be an effective conductor of heat while maintaining mechanical strength, which is especially critical in rockets, airplanes, and electric cars, where components face vibrations, shocks, and repeated temperature and stress changes.
While copper might seem like the obvious choice due to its excellent thermal conductivity, it poses challenges for 3D printing with infrared lasers. Copper’s high thermal conductivity rapidly disperses heat during the printing process, and its reflective surface makes laser energy absorption difficult. Additionally, pure copper is relatively soft, allowing thin structures to deform under mechanical loads.
Aluminum bronze, an alloy with about 10% aluminum and 1% iron mixed with copper, offers a feasible alternative. It’s easier to print and mechanically stronger than pure copper, though with lower thermal conductivity.
However, 3D printing introduces another challenge. Metals tend to cool and solidify very quickly during printing, which can lead to uneven chemical compositions and unstable microscopic structures. These tiny variations can influence the final strength and flexibility of the component.
After examining the internal structure of 3D-printed aluminum bronze with a scanning electron microscope, the scientists hypothesized that post-print heat treatment could improve its internal organization.
They subjected samples to an electric furnace at three different temperatures—300°C, 400°C, and 500°C—for three hours each. The samples were then tested and compared to untreated aluminum bronze.
Temperature proved to be a key factor.
Heating to 300°C or 400°C actually degraded the material’s properties. These temperatures promoted the formation of unstable phases within the alloy, reducing its ductility and increasing brittleness.
In contrast, heating to 500°C brought about significantly different results. At this higher temperature, atoms could move and repopulate the alloy more effectively, smoothing out chemical irregularities and stabilizing the microscopic structure. The outcome was a much better compromise between strength and flexibility.
The researchers emphasize that this study demonstrates why standard heat treatments used for traditionally manufactured metals cannot be directly applied to 3D-printed materials without thorough testing.
The next step involves assessing whether heating aluminum bronze to 500°C compromises its heat-conducting abilities. If it retains good thermal conductivity, this approach could offer a practical method for manufacturing durable, complex cooling components for high-performance electronics in electric vehicles, aircraft, rockets, and other advanced technologies.