Farsoon unveils the FS621M-Cu for large-scale copper 3D printing
The machine uses four 1000W ytterbium fiber lasers (1060–1080 nm) to handle the reflectivity of copper alloys like CuCrZr
Copper alloys are essential in aerospace combustion chambers due to their exceptional thermal conductivity, ductility, and resistance to corrosion. However, their high reflectivity to near-infrared lasers—especially at 1064 nm—has historically limited their viability in metal 3D printing. Farsoon, one of China’s leading industrial metal 3D printing companies, began tackling this challenge in 2017 by developing a copper-compatible process on its FS271M platform. In 2023, the company advanced this expertise through a collaboration with a leading aerospace manufacturer to co-develop a copper-focused, large-format system: the FS621M-Cu.
Built on the proven FS621M platform with a 620 × 620 × 1100 mm build envelope, the FS621M-Cu uses four 1000W ytterbium fiber lasers (1060–1080 nm) to handle the reflectivity of copper alloys like CuCrZr. This allows for consistent, high-quality printing of large, complex aerospace parts that were previously unprintable.
Among its most significant achievements is the 3D printing of liquid rocket engine thrust chamber liners—components traditionally made through costly and time-intensive spinning, machining, and brazing. Farsoon’s LPBF process enables these chambers to be printed monolithically, integrating optimized cooling channels, reducing assembly steps, enhancing heat transfer, and improving engine performance.
Copper’s inherent properties—high conductivity and reflectivity—create risks such as porosity and warping during printing. Farsoon addressed this with innovations including anti-reflective chamber coatings, precise thermal management, and customized high-power laser parameters.
In August 2023, Farsoon’s aerospace partner printed a thrust chamber liner measuring 600 mm in diameter and 850 mm in height—among the largest monolithic copper alloy parts ever made via AM. The part achieved near-theoretical density (8.86 g/cm³), thermal conductivity over 345 W/(m·K), and pore-free internal structures. Post-build polishing of cooling channels further improved engine efficiency.
Mechanical tests on printed specimens revealed top-tier thermal performance: conductivity ≥345 W/(m·K), diffusivity ≥95 mm²/s, and specific heat capacity ≥0.35 J/(g·K). With optimized powder quality and LPBF parameters, the customer surpassed design requirements by over 50%, while cutting lead times to 15–20 days and costs by up to 75%.
