Copper Laser Additive Manufacturing Using New Blue and Green Lasers
Additive manufacturing allows complex geometries and multi material construction of parts, which would otherwise be difficult to produce using conventional technologies.
However, to date use of additive manufacturing technology with copper alloys has been extremely limited due to the inherent high reflectivity of copper for the most commonly used infrared laser sources operating at a wavelength of around 1064 nm, which makes beam to material coupling and melting of copper alloys more difficult and typically unstable.
Recent advancements in laser technology have led to the production of new blue and green lasers operating at a shorter wavelength range between 420 and 559nm. These lasers have recently become available at sufficient high beam quality and power levels to enable defect free processing of pure copper and copper alloys for the first time.
This paper will discuss recent research conducted in a joint project by Fraunhofer IWS (Dresden, Germany) and Fraunhofer USA CMW-Laser Applications Division (Plymouth, Michigan USA) using two additive processes Laser Directed Energy Deposition (L-DED) and Laser Powder Bed Fusion (L-PBF) with a green laser source to process pure copper and high-strength copper alloys in order to produce additively manufactured demonstrator parts.
Results from both L-DED, L-PBF and hybrid process combinations of both technologies will be presented.
Results from laser process development and detailed analysis of the resultant materials properties produced by additively manufactured copper components will be presented.