Feasibility Study of Ferromagnetic Particulate Path Diversion in Additive Manufacturing

The use of electromagnetic actuator components typically involves a coil comprised of a stack-packed continuous winding, usually layered, and a core material of soft iron or at least a solenoid, similarly constructed, simply with an air core. These are used widely across, but not limited to, several industries such as automotive, aerospace, medical, and various electronics. Their application to additive manufacturing (AM), and in particular to improvement of catchment efficiency, is a somewhat newly ventured avenue and the use of permanent magnets in their place to simulate their presence is of similar vein. The objective of this thesis is to introduce a novel but constructive approach to implement catchment efficiency improvement with regard to ferromagnetic particles by increasing their density in proximity to the melt pool through introduction of a magnetic (or electromagnetic) field. This field acts to produce a lensing or concentric constriction of the particle stream above, and as its contents near and enter the AM build zone. The particle dynamics and stream studied have a purely vertical initial velocity and steady flow rate. Not discussed are melt pool effects from the introduced magnetic field, or angled AM particle streams. Four analytical methods to determine the magnetic (B) field either on or off the axis of a solenoid are first studied, then narrowed to two to verify Matlab programming from an established benchmark. A finite element (FEA) model is constructed to provide simulations and a soft iron particle is introduced to further determine validity of Matlab programming for both air core and iron core constructs. A similar process uses permanent magnets in place of a coil. A parametric sweep in the FEA software generates force data for post-processing in Matlab to produce particle displacement plots using differential equations to complete this technique. The aforementioned simulation process serves as confirmation of particle path diversion and additional experimental validation is proposed. The experiments would substantiate particulate path diversions in the presence of the permanent magnet configuration, substituted for a coil configuration, to confirm the simulated construct to be authentic regarding its required particulate force effects