My technical wording is bad. But, let me put the picture as clear as possible.
My idea is that if we can make magentic flux or field lines in a desired shape, we can use those field lines to align magnetic particles to create a shape. Lets say a cube. The field lines are in the shape of a cube and in such an environment, if we release iron granular particles, they might get arranged in 3D. If this is possible, we can make a new way of 3D printing.
Let me know if this is possible.