Medium carbon steel (EN8) substrates with different Surface Roughness (SR) were deposited by Titanium Nitride (TiN). The research work was carried out to investigate the effect of SR and thickness of the thin film coating on substrate structure and tribological properties. EN8 rectangular blocks (60x10x10mm) were used as substrate materials. The variations in SR were achieved by using emery paper on one side and by machining the other side. Scratch tests were conducted and they showed that TiN coatings on substrate with higher SR (1.2 µm) exhibited less adhesion strength compared to TiN coatings on substrate with a lower SR (0.4 µm). Scratch tests also indicated poor adhesion with an increase in the SR of the substrate. The traction force and Coefficient of Friction (COF) were measured during the dry scratch tests under different normal loads, sliding speeds and ramp load conditions. To examine the morphologies of coated substrates and worn surfaces after the scratch test, optical microscopy was utilized. It was found out that TiN coating with a substrate roughness of 0.4 µm exhibited a lower COF and its wear mechanism was adhesive wear. It was experimentally found out that by decreasing the SR of the substrate coatings, wear resistance could be improved.

3D printing is a promising digital manufacturing technique that produces parts with layer by layer. The influence of process parameters is investigated for ABS material in fused deposition modelling (FDM). This work aimed to determine the surface roughness of 3d printed parts of the ABS material with varied parameters of infill height and infill density. The results of the test show that the, surface roughness is higher (11.6mm) at 20% infill density with 0.26mm infill layer height. Also, ABS material surface shows good finish (lower surface roughness) at 100% infill density with 0.06mm infill layer height. The infill layer height clearly visible under microscope at higher infill layer height with all the infill densities.

India is the third largest coconut cultivating country in the world. South India states are the predominant coconut cultivating area in India. Coconut shell (CS) and coconut shell ash (CSA) are unavoidable by-products from agricultural industry. As a part of solid waste management, the investigation was carried out to evaluate the effect of replacing cement by CSA and coarse aggregate by CS. The replacement level was considered as 5%, 10%, 15%, 20%, 25% and 30% in both cement and coarse aggregate by CSA and CS respectively. Normal strength concrete was considered in this investigation. The density and mechanical properties of concrete such as 28 days cured compressive strength and flexural strength were determined. Using 3D graphical analysis, the optimum replacement of cement and coarse aggregate was predicated in this investigation.

The aim of the work is to study the suitability of Prosopis juliflora as a partial replacement of coarse aggregate. Concrete mix is made with varying proportions of Prosopis juliflora stem replacing the coarse aggregate up to 2.5%, 5%, 7.5%, 10 % and 12.5 % to the concrete percentage and results to increase in the compressive strength of the concrete cube up to 10 % was noted. Water absorption is up to 0.9 % and maximum value of flexural strength achieved at 3Mpa. Maximum strength of 34Mpa Compressive strength was achieved. Concrete with Light weight and less thermal conductivity was achieved by using Prosopis juliflora wood as partial replacement for coarse aggregate.

Traditional fused deposition modeling (FDM) is an additive manufacturing method in which a part is fabricated using layer upon layer approach. Due to the imminent nature of this approach, support structures are needed to sustain overhanging elements of the parts, particularly for the production of metal components and complex geometries. Several works are going on to minimize the usage of supports by using improved support strategies. However, the use of different support strategies at different pre-defined machine settings may lead to varied properties of the final printed part. In this work, the influence of support strategies on flexural properties at four different parameters is experimentally determined in the fused deposition modeling process. Two support strategies, Line and Grid, are adopted while fabricating the same 3D part at three different printer parameter settings. The flexural properties of the samples are compared for assessing the impact of two support strategies, as well as the support material usage and printing time. Results reveal that two support methods lead to varied flexural strength and print qualities at varied parameters.