A method for extruding composite materials on a substrate includes feeding a first material into a first channel and a second material, used to maintain a shape of the first material, into one or more second channels residing on at least one side of the first channel, merging the flows of the first and second materials into a single flow in which the second material surrounds the first material, applying the single flow to a substrate to produce at least one composite material, and post-processing the composite material to form a solid.