## 3 Results
This specimen would typically be discarded but was included in order to accurately portray all results and findings. Specim B shows how a specimen made with an intentional gap in the material deposition paths would be expected to perform. Specim A (\(-\)3.2 mm overlap) performed very differently, even though it was taken from the same build. Specim A had the highest ductility of the tested specimens by a notable margin. The results of the experimental tensile tests show that, in general, AFSD builds with a greater overlap width can expect greater and more consistent mechanical properties. As such, a build with a 0.0 mm overlap, or a small gap, will likely exhibit inferior tensile properties and inconsistent performance even within the same deposition. For each fractured tensile specimen, SEM was used to perform post-mortem analysis of the fracture surfaces. Figure 13a shows the fracture surface of the specimen with 0.0 mm of overlap (A), which had the lowest quantified performance. This image shows the central portion of the fracture surface undergoing ductile fracture by showcasing the cup-and-ball, or dimpling, features commonly seen with micro-void coalescence seen in ductile failure, but this image also shows a very high angle of fracture with many sharp, flat regions indicative of poor ductility. Figure 13b shows the fracture surface of the specimen with 3.2 mm of overlap (A), which has a larger region of typical ductile features covering the left half of the image and sharp ridges on the right side containing some small pockets of shallow dimpling. Figure 13c,d show the surface of the specimen with 9.5 mm of overlap (A), which had the highest yield and ultimate strengths of the tested specimens. Figure 13c shows similar behavior as Figure 13b, with half of the fracture surface covered by dimpling, showcased at a higher magnification in Figure 13d, while the rest of the surface shows several layers of ridge-like features. Figure 12: Quasi-static data for AFSD overlap specimens compared to feedstock AA7075. The observations made from the fracture surfaces confirm the results of the experimental tensile testing, with specimens undergoing a relatively low amount of ductility before complete failure compared to the feedstock specimen. The sharp angle of the resultant fracture surfaces compared to the direction of the applied force, especially in Figure 13a, suggests that the specimen experienced failure due to resultant shear stresses. The highest amount of ductility from the tested specimens only just exceeded half of that of the tested feedstock material, as shown in Table 4. These specimens are detailed and discussed separately in Figure 14.  
Figure 14a,b show the fracture surface of the specimen with \(-3.2\) mm of overlap (A), the specimen with the highest ductility from the overlap build specimens. Figure 14a shows a representative fracture surface primarily covered in dimpling, showcased in Figure 14b, which is expected given its relatively higher ductility. The ridge-like features previously observed are present in this fracture surface as well, primarily in the upper-left region of the image, but these ridges have small, dimpled regions across the surface. Figure 14c,d show the fracture surface of the specimen with \(-3.2\) mm of overlap (B), which failed almost immediately upon mechanical loading. This fracture surface shows a wide range of features, with sharp, jagged cliffs across the bottom half of the surface, and a relatively smooth region across the top half, with very large cracks throughout the entire surface. It is worth noting a small region of ductility, magnified in Figure 14d, where dimpling occurs  
Figure 13: (**a–c**) SEM of tensile specimen fracture surfaces for non-negative overlap builds. (**d**) High magnification SEM image of dimpling effect from the specimen with \(9.5\) mm of overlap. in a small pocket amidst several jagged points and cracks was observed. This specimen failed rapidly with minimal ductility.