Fabrication of graded structures by extrusion 3D Printing

3D Printing allows the cost-effective and fast fabrication of parts with intricate/complex external and internal structure through the controlled addition of thin layers of material. This way, heterogeneous structures, i.e. structures with non-uniform density, can be constructed. In the present paper a method for the production of gradient structures with extrusion-type 3D Printing is discussed. The method involves three main steps: defining the geometry and material distribution of each layer in the form of a grayscale image, generating a set of points distributed according to the gray tone of the image and constructing a continuous path through the points for guiding material deposition by the 3D printer. In order to better present and test the method, two test cases of gradient structures are examined.