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In the current technological evolution, additive manufacturing is taking a lead role in manufacturing of components for both prototyping as well as finished products. Metallization of the polymer parts has high potential to add value in-terms of metallic luster, improved strength, long shelf-life and better radiation resistance. Standard acid copper plating process has been adopted for deposition of copper on polymer parts manufactured by fused deposition modelling (FDM) technique. The parameters namely the etching time, voltage and the surface finish of the manufactured FDM parts are studied for their influence on the surface quality. Experiments have been designed using design of experiments strategy. Experiments have been conducted and surface roughness has been measured. Influence of each of the three parameters has been discussed in detail. For the reported process the optimal value of etching time of Acrylonitrile Butadiene Styrene (ABS) has been found in the range of 30 to 60 minutes along with applied voltage in the range of 1.5 to 2.5 Volts for copper electroplating.

Fused deposition modeling (FDM) is one of the most popularly used additive manufacturing techniques to manufacture complex geometry thermoplastic polymer parts. In FDM, during solidification process, the extruded filament called as roads gets bonded with the adjacent roads forming a layer and hence the entire part. Time-dependent thermal behavior of the polymer material decides the structural integrity of the part that is manufactured. An attempt has been made to analyze the effect of temperature on bond formation. A new mathematical model is developed to relate time, temperature and the extent of bonding. Parts are manufactured at different extrusion temperatures, and tensile tests are conducted to evaluate the strength and its dependency on extrusion temperature. Fractured specimens are observed under scanning electron microscope to understand the bonding between the fused polymer roads. Results show good agreement between the proposed mathematical model and the experiment results.

Cleft lip occurs due to incomplete joining of the tissue that forms the upper lip resulting in an opening in the upper lip. This opening is in the form of a slit and is large extending up to the nose. Many methods have been suggested in repairing the cleft lip. As a part of post-surgical treatment, the nasal deformity has been an issue. Nasal conformer is a post-surgical aid that helps the patients to keep their nasal deformity in control. The present work aims in design and manufacturing of this nasal conformer for the much needy poor patients. Computer Aided Design (CAD) techniques are used to model the nasal conformer by taking the dimensions of the various aged group people ranging from 6 months to 16 years old. Based on that, 5 such sizes have been arrived. These CAD models have been manufactured using Fused Deposition Modeling (FDM) technique to prepare the final pattern for molding process. Once the molds for the nasal conformer have been created, the final parts have been casted using Silicone material. The final casted nasal conformers are being proposed to be distributed to the needy.

The present research work aims at understanding the effect of fused deposition modelling process parameters on tribological properties such as friction and wear rate. Two pin-on-disc parameters, namely normal load and sliding speed have been chosen. Orientation angle of the part is chosen as the third varying parameter. Test specimens are manufactured as per the design of experiments set-up. Response surfaces and interaction effects of process parameters are studied through response surface methodology. Analysis of variance results indicate that there is substantial interaction effect of build orientation angle on comparison with the other two parameters on the tribological properties. Scanning electron microscope micrographs of the worn surfaces reveal the importance of part build orientation and its contribution towards surface strength properties. The tribological studies conclude that cracks are formed in the specimens when tested at high load, high speed and low part build orientation angle of the part.

Fused filament fabrication (FFF) is a polymer extrusion-based additive manufacturing technique. In FFF process, semi-molten material is deposited in the form of strands and hence get bonded upon solidification through the formation of “neck”. These bonds play a crucial role in deciding the mechanical properties of FFF manufactured part. Bonding between the strands are governed by thermal energy (or in other words), a heating–cooling effect needs to be considered for the evaluation of FFF part mechanical properties. These are influenced by the FFF process parameters namely, extrusion temperature, layer thickness, part orientation, and raster orientation. This study attempts to develop a new mathematical model to establish a relationship between “neck radius” and “time” at different raster orientations. This paper explains the relationship between neck growth and raster orientations in FFF process. A new mathematical model has been developed by equating the work done by the surface tension and work done due to viscous forces by the molten polymer strands. From the developed mathematical model, the neck radius is evaluated with varying raster orientation (Ø°) (0 < Ø ≤ 900). The study also involves an experimental approach to establish the fact that neck growth (in the form of strength) is influenced by the FFF parameter settings the FFF parameter settings influence neck growth (in the form of strength). A face-centered design of experiment is considered, 30 experiments are performed and analyzed for responses like tensile strength, flexural strength, and volumetric shrinkage. Analysis of variance (ANOVA) is performed to validate statistical stability the proposed model. Response surface methodology is considered to study the interaction behavior of each FFF process parameters on each response parameters. From the developed mathematical model, the absolute neck growth at 30°, 45°, 60° and 90° raster orientations are obtained as 0.35 mm, 0.29 mm, 0.30 mm and 0.13 mm, respectively. The current study indicates the inverse relationship between neck growth and raster orientation. Study shows that mechanical properties highly depend on parameters that directly influence part orientation, raster orientation, and the extrusion temperature. Present study shows that higher mechanical properties can be achieved at lower raster and part orientation which is in greater agreement with the proposed mathematical model results.