Why is Metal based Powder Bed Fusion so Complex???

The world of Additive Manufacturing is very complex. The fortune to work in the sub field of powder based metal additive manufacturing has exposed me to a multi dimensional world of process parameters, material properties, calibration of the printer, build plan and post processing. Each of the above mentioned broad categories have a fractal of parameters that makes it difficult to mathematically model a simple metal powder based additive manufacturing problem. Honestly, after a certain point of designing experiments, it becomes a brain draining process to try to understand the physical aspects that govern the process or what weights do each of the many parameters carry on the final printed sample. Parameters like hatch spacing, laser power, laser speed, type of support structures, thermal conductivity of the powder, hatch angle change with every layer, scanning pattern, build orientation, downskin thickness, laser jump speed, oxygen content in the raw material, offset to contour, number of contours etc. Yeah we are dealing with an 'n' dimensional problem when we talk about metal printing. The only question is what is the number would one assign to the variable 'n'?

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