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In the current scenario, a decline in the natural deposits of copper and its alloys has called for the efficient usage of bronze in mechanical components. The development of additive manufacturing processes such as Directed Energy Deposition (DED) provides an opportunity to address this issue by replacing complete bronze components such as worm wheels with parts made of less critical raw materials and provided with bronze coatings on the wear-active interfaces. Therefore, this current work focuses on evaluating the deposition of CuSn10 on a steel substrate using DED. Four types of specimens are manufactured, three having deposition of CuSn10 on the steel substrate and one specimen having an initial deposition of CuSn10 + 316L mixture followed by CuSn10. The laser power for the deposition process was varied through the thickness of the deposition with values varying between a minimum of 600 W to a maximum of 1100 W. The specimens were subjected to wear testing under dry conditions to evaluate their friction behavior and to check for debonding between the substrate and deposition. The effect of different laser power on porosity, microstructure, and microhardness was evaluated. The results, when compared with wrought CuSn10, indicated that the DED CuSn10 can be a probable replacement for wrought CuSn10 in worm wheels.

The present work investigates cellular materials that can be potentially used as a replacement of solid implants owing to their mechanical properties and biocompatibility. More specifically, titanium alloy (Ti6Al4V) cellular materials of three different topologies were considered to study the effect of the degree of irregularity. Cubic regular, cubic irregular and trabecular structures were manufactured using Laser based powder bed fusion (LB-PBF) process. The LB-PBF process had an impact on the strut thickness of the samples. Samples were subjected to micro computed tomography to understand the geometrical deviations and to use the actual geometry for finite element analysis. Mechanical properties such as Young's modulus and strength were derived from compression and tensile testing. The results indicate that the Young's modulus was between 6 and 17 GPa, which were closer to the values of human cortical bone. The finite element analysis results showed a good correlation with the tensile test results as well. Furthermore, Gibson–Ashby model is used to study the effect of cell topology on the structural behavior. The model indicated that the misalignment of nodes of cubic regular structures to form irregular structure, transformed the stretching dominated behavior of cubic structures to bending dominated behavior like trabecular structures. Finally, the regular structures appeared to be much more prone to catastrophic failure than irregular and trabecular structures. Both visual observation of experimental testing and FE analysis explained this difference as result of different modes and zones of failures.