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This paper aims to focus on the application of multi-attribute decision-making methods (MADMs) to ascertain the optimal machining parameters while turning Ti-6Al-4V alloy under minimum quantity lubrication (MQL) conditions using Jatropha-curcas oil (JCO) bio-based lubricant.

The experiments were designed and performed using Taguchi L27 design of experiments methodology. A total of 27 experiments were performed under MQL conditions using textured carbide cutting tools on which different MADMs like Analytic hierarchy process (AHP), Technique for order preference by similarity to ideal solution (TOPSIS) and Simple additive weighting (SAW) were implemented in an empirical manner to extract optimize machining parameters for turning of Ti-6Al-4V alloy under set of constrained conditions.

The results evaluated through MADMs exhibit the optimized set of machining parameters (cutting speed V_c = 80 m/min, feed rate f = 0.05 mm/rev. and depth of cut a_p = 0.10 mm) for minimizing the average surface roughness (Ra), maximum flank wear (Vbmax), tangential cutting force (Fc) and cutting temperature (T). Further, analysis of variance (ANOVA) and traditional desirability function approach was applied and results of TOPSIS and SAW methods having optimal setting of parameters were compared as well as confirmation experiments were conducted to verify the results. A SEM analysis at lowest and highest cutting speeds was performed to investigate the tool wear patterns. At the highest speed, large cutting temperature generated, thereby resulted in chipping as well as notching and fracturing of the textured insert.

The research paper attempted in exploring the optimized machining parameters during turning of difficult-to-cut titanium alloy (Ti-6AL-4V) with textured carbide cutting tool under MQL environment through combined approach of MADMs techniques. Ti-6Al-4V alloy has been extensively used in important aerospace components like fuselage, hydraulic tubing, bulk head, wing spar, landing gear, as well as bio-medical applications.

The purpose of this paper is to investigate the process capability of three-dimensional printing (3DP)-based casting solutions for non-ferrous alloy (NFA) components.

After selection and design of benchmark, prototypes for six different NFA materials were prepared by using 3DP (ZCast process)-based shell moulds. Coordinate measuring machine has been used for calculating the dimensional tolerances of the NFA components. Consistency with the tolerance grades of the castings has been checked as per IT grades.

The results of process capability investigation highlight that the 3DP process as a casting solution for NFA component lies in ±5sigma (s) limit, as regards to dimensional accuracy is concerned. Further, this process ensures rapid production of pre-series industrial prototypes for NFA. Final components prepared are also acceptable as per ISO standard UNI EN 20,286-I (1995).

This research work presents capability of the 3DP process supported with experimental data on basis of various process parameters for the tolerance grade of NFA castings. These statistics can help to enhance the application of 3DP-based NFA casting process in commercial foundry industry.

The purpose of this paper is to fabricate acrylonitrile-butadiene-styrene (ABS)/high impact polystyrene (HIPS) based multi-material geometries using a low cost polymer printer. At the same time, efforts have been made to investigate the mechanical characteristics of the obtained prints and to perform the optimization using the Taguchi-Grey (TGRA) method.

Initially, the feedstock materials were in-house fabricated in the form of filament wires, workable with fused filament fabrication (FFF) technique, of 1.75 ± 0.1 mm diameter by using a single screw extruder. Multi-material structures were fabricated using variable parameters (such as: raster angles, layer height, fill density and solid layers) and the experimentation was conducted as per Taguchi L18 array. Mechanical responses obtained by performing tensile, impact and bending test were studied in response to input variables and ultimately optimized settings were obtained, for individual as well as multiple parameters). Scanning electron microscopy (SEM) analysis was performed to analyze the fractured surfaces.

The Signal/Noise (S/N) plots for the quality characteristics highlighted that selected input parameters significantly influenced the obtained values for tensile strength, impact strength and flexural strength. Micrographs of the fractured specimens showed the occurrence of brittle fracture with higher levels of perimeter, infill density and solid layers. The extent of delamination was also increased under the bending load and further increased by increasing solid layers.

The results of the study strongly advocated the utility of fabricated multi-materials structures in automotive, aerospace and other manufacturing industries.

This work represents the fabrication, testing and analysis of polymer-based multi-material structures for engineering applications.

The purpose of this study is to investigate dimensional accuracy (Δd), surface roughness (Ra) and micro hardness (HV) of partial dentures (PD) prepared with synergic combination of fused deposition modelling (FDM) assisted chemical vapour smoothing (CVS) patterns and conventional dental casting (DC) from multi-factor optimization view point.

The master pattern for PD was prepared with acrylonitrile butadiene styrene (ABS) thermoplastic on FDM set-up (one of the low cost additive manufacturing process) followed by CVS process. The final PD as functional prototypes was casted with nickel–chromium-based (Ni-Cr) alloy by varying Ni% (Z). The other input parameters were powder to water ratio P/W (X) and pH value (Y) of water used.

The results of this study suggest that for controlling the Δd and R_a of the PD, most important factor is X, followed by Z. For hardness of PD, the most important factor is Z. But from overall optimization viewpoint, the best settings are X-100/12, Y-10 and Z-61% (in Ni-Cr alloy). Further, based upon X-bar chart (for HV), the FDM-assisted DC process used for preparation of PD is statistically controlled.

This study highlights that PD prepared with X-100/12, Y-10 and Z-61% gives overall better results from multi-factor optimization view point. Finally, X-bar chart has been plotted to understand the statistical nature of the synergic combination of FDM, CVS and DC.

The purpose of this paper is to design and manufacture an intelligent 3D printed sensor to monitor the re-occurrence of diaphragmatic hernia (DH; after surgery) in bovines as an Internet of Things (IOT)-based solution.

The approach used in this study is based on a bibliographic analysis for the re-occurrence of DH in the bovine after surgery. Using SolidWorks and ANSYS, the computer-aided design model of the implant was 3D printed based on literature and discussions on surgical techniques with a veterinarian. To ensure the error-proof design, load test and strain–stress rate analyses with boundary distortion have been carried out for the implant sub-assembly.

An innovative IOT-based additive manufacturing solution has been presented for the construction of a mesh-type sensor (for the health monitoring of bovine after surgery).

An innovative mesh-type sensor has been fabricated by integration of metal and polymer 3D printing (comprising 17–4 precipitate hardened stainless steel and polyvinylidene fluoride-hydroxyapatite-chitosan) without sacrificing strength and specific absorption ratio value.

This research work aims to make an effort to investigate the effect of fused deposition modelling (FDM) process parameters on the surface finish of acrylonitrile butadiene styrene (ABS) replicas (as pre-processing stage), followed by chemical vapor smoothing (CVS) process (as a post-processing stage) as a case study.

The Taguchi L18 orthogonal array has been used for optimizing process parameters of FDM and CVS processes.

This study highlights that orientation and part density, and the interaction between these two have a significant effect on the surface finish at the pre-processing stage of FDM. However, after post-processing with CVS, there is hardly any influence of pre-processing FDM parameters.

The study highlights that for improving the productivity of the FDM process, the parametric optimization of process may be made on the basis of production cost and time in place of surface finish of ABS replicas. The results obtained have been verified by performing the confirmation experiments.

Additive manufacturing (AM) is one of the latest and most advanced technologies that are continuously expanding into various field applications. Undoubtedly, fused deposition modeling (FDM) is one of the oldest and extensively used AM technologies not only because of the advantage of low cost, comparatively moderate production speed and negligible wastage but also due to acceptance of a wide range of thermoplastics, reinforced and blended feedstock for making the end product suitable for service. The purpose of this work to perform mechanical characterization of standard samples printed on FDM with acrylonitrile butadiene styrene (ABS), shape memory polymer (SMP; make Polyflex^TM) and ABS/Polyflex^TM blend and a comparative study from AM view point.

A low-cost desktop-based FDM setup was used for the fabrication of the test specimens under different processing conditions. Experiments were conducted as per obtained control log, and statistical analysis was conducted to understand the effect of selected variables in response of measured properties. Further, scanning electron microscopy-based micrographs were analyzed to understand the fracture mechanisms.

The obtained results highlighted that the mechanical properties of FDM parts are strongly influenced by the selected process variables. However, in case of most of the measured properties, selection of suitable feedstock has dominated the other input variables. Further, the results of test parts made with in-house developed ABS/SMP blend have showed the attainment of remarkable values of both strength and elasticity.

This work is held to empower the use of FDM technology to fabricate advanced and robust components for serving highly demanding applications.

This paper aims to focus on the changes in thermal and surface characteristics of acrylonitrile butadiene styrene (ABS) material when exposed to chemical vapours for surface finishing. The poor surface finish and the dimensional accuracy of the fused deposition modelling parts (of ABS material) because of the stair-stepping hinder their use for rapid tooling applications, which can be improved by vapour finishing process. The differential scanning calorimetry (DSC) tests are performed to investigate the thermal behaviour of ABS thermoplastic after vapour finishing.

The hip prosthesis replica has been used to highlight the efficacy of chemical finishing process for intricate and complex geometries. The replicas are treated with chemical vapours for different durations. The DSC tests are performed along with surface roughness, surface hardness and dimensional measurements of exposed replicas and compared with unexposed replica.

The longer finishing time, i.e. 20 s, manifested higher melting peak temperature, higher melting enthalpy and higher heat capacity along with smoother and harder surface as compared with unexposed replica. The finishing process enhanced the bonding strength and the heat-bearing capacity of ABS material. The vapour finishing process enhanced the thermal stability of the material which may extend its sustainability at higher temperatures.

The improved thermal stability of ABS thermoplastic after chemical vapour finishing has been demonstrated. This advancement allows the use of ABS in functional tooling suitable for small production runs with higher flexibility and lead time savings.

The heat effects associated with phase transitions as a function of temperature are studied in case of replicas finished with chemical vapours. The relationship between melting enthalpy and surface characteristics has been ascertained.

In this study the friction and wear behavior of fused deposition modeling (FDM) parts fabricated with composite material and acrylonitrile butadiene styrene (ABS) material feedstock filament were realized and compared under dry sliding conditions.

The tests were performed by applying the load of 5, 10, 15 and 20 N with sliding velocity of 0.63 m/s for the duration of 5 and 10 min at room temperature.

The results highlight various wear mechanisms such as adhesion, abrasion and fatigue during the investigation. It was observed that the wear volume, friction force, friction co-efficient and temperature were sensitive to the applied load and time duration. The composite material showed a remarkable improvement in wear properties as compared to the ABS material.

The investigations reported in the present research work is based on comparative analysis (of composite material and ABS material feedstock filament). The results may be different in practical applications because of different operating conditions.

The parts fabricated with proposed composite material feedstock filament are highly wear resistant than basic ABS filament. This may lead to the development of better wear resistance components for numerous field applications.

The potential of this research work is to fabricate FDM parts with composite material feedstock filament to cater need of wear resistant industrial components.

Three-dimensional printing (3DP) is an established process to print structural parts of metals, ceramic and polymers. Further, multi-material 3DP has the potentials to be a milestone in rapid manufacturing (RM), customized design and structural applications. Being compatible as functionally graded materials in a single structural form, multi-material-based 3D printed parts can be applied in structural applications to get the benefit of modified properties.

The fused deposition modelling (FDM) is one of the established low cost 3DP techniques which can be used for printing functional/ non-functional prototypes in civil engineering applications.

The present study is focused on multi-material printing of primary recycled acrylonitrile butadiene styrene (ABS), polylactic acid (PLA) and high impact polystyrene (HIPS) in composite form. Thermal (glass transition temperature and heat capacity) and mechanical properties (break load, break strength, break elongation, percentage elongation at break and Young’s modulus) have been analysed to observe the behaviour of multi-material composites prepared by 3DP. This study also highlights the process parameters optimization of FDM supported with photomicrographs.

The present study is focused on multi-material printing of primary recycled ABS, PLA and HIPS in composite form.