Multi-beam laser additive manufacturing

Today, Laser Additive Manufacturing (LAM) is typically performed using a single beam with power up to multiple-kilowatts. The associated high heat input and limited process control hampers tight manufacturing tolerances and the applicable material spectrum. This paper highlights the development of Multi-beam LAM technology to address the shortfalls of today's technology and to broaden the applicability to many industries. Multi-beam LAM deploys several low power beams, each precisely controllable with a minimum heat input thus providing the capability to tailor the applied energy to the specific needs of the application. The single beams either work in parallel to scale productivity without sacrificing precision or in close proximity creating desired heat profiles. This new approach is scalable in productivity through multiplication and is expected to allow deposition of difficult to coat materials through tailored heat profiles. Advances are expected in near net shape manufacturing of complex structures with fine features and high dimensional accuracy. A compact prototype processing head for Multi-beam LAM was designed and built to investigate the capability of the new technology. The head incorporates latest high-brightness diode laser technology and a compact powder nozzle design. Two laser beams are being emitted, a stationary beam with fixed position on the work piece and a movable beam that can be positioned relative to the stationary beam. A very effective solution with high spatial resolution and fast actuation was developed for steering the movable laser beam. The movable beam cannot only be set to a fixed position but it can also be scanned at high frequencies. The power of both beams is individually controlled. Ongoing process investigations and future MB-LAM target specific applications for vehicles, jet engines and medical devices serving the automotive, aerospace, medical and defence sector. Initial results are being presented.