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Additive manufacturing is becoming increasingly widespread and has developed very dynamically in recent years. For the processing of metals, powder or wire is usually used as the feedstock. The energy source used in wire-based processes is usually electric arcs or lasers. In this contribution, a technological approach for additive manufacturing of metal structures by induction melting with pulsed generator power is used. Therefore, the principle of oscillating Lorentz forces is utilized in this approach and analytically investigated with the aid of a FE simulation model. In the experiments, a continuously fed steel wire is inductively melted and deposited dropwise onto a substrate heated to different preheating temperatures without the use of a nozzle or crucible. [ABSTRACT FROM AUTHOR]

Induction heating is a fast, reproducible, and efficient heating method used in various manufacturing processes. However, there is no established additive manufacturing (AM) process based on induction heating using wire as feedstock. This study investigates a novel approach to AM based on inductive heating, where a steel wire is melted and droplets are detached periodically using a two-winding induction coil. The process parameters and energy input into the droplets are characterized. The induction generator exhibits a sluggish response to the excitation voltage, resulting in a lag in the coil current. The process is captured using a high-speed camera, revealing a regular droplet formation of 14 Hz and uniform shapes and sizes between 2.11 and 2.65 mm in diameter when operated within an appropriate process window. Larger drops and increased spatter formation occur outside this window. The proposed method allows for the production of droplets with almost spherical shapes. Further analysis and characterization of droplet formation and energy input provide insights into process optimization and indicate an overall efficiency of approximately 10%. [ABSTRACT FROM AUTHOR]