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The current review is focuses on a comprehensive investigation of the process parameters such as height of layer, orientation, speed of printing, Air gap, fill density, Infill structure, Raster angle, Width of raster, temperature of bed and how they influence the tribological behavior of the ABS specimens fabricated using the Fused Deposition Modelling (FDM), The tribological properties of FDM build parts are highly affected by these process parameters. Due to this, researchers have explained optimum values of these parameters to enhance the tribological behavior. According to the application, for which the part is produced, these process parameters should be chosen cautiously. For a particular demand, some of process parameters are important than rest, so there is need to be identify and optimize these important parameters for these researchers have investigated and employed different Design of Experiments (DOE) which are discussed in this paper. Another way of improving tribological behavior of ABS is the addition of material such as, such as graphite, PTFE, Zirconia, CaCO3, and, carbon fiber etc. The addition of materials to polymers has a significant impact on the wear resistance quality. This not only affect wear but also improve the friction coefficient as compare to the pure polymer. This paper aims at reviewing recent research on improving tribological behavior of ABS parts produced using FDM process.

Fused filament fabrication (FFF) is one of the additive manufacturing processes which is used widely due to its ease of usage and low cost. The final quality of parts in the FFF process is determined by a careful selection of process parameters, as it is required to understanding the physical phenomena of process variables and their impact on mechanical properties. This study involves the independent analysis of five process variables i.e. printing nozzle temperature, layer thickness, raster orientation, speed/feed rate and infill pattern. Taguchi L27 orthogonal array opted to investigate the tensile strength of Polylactic acid (PLA) specimens. By using this technique, the number of experimental reduced from 243 to 27 experiments. These specimens are fabricated based on ASTM D-638 tensile standard design. Artificial Neural Network tool has opted by using MATLAB software for training and testing of data. Some notable observations based on our experimental investigations carried out for process parameter optimization was that for the least change, layer thickness of 200 μm, nozzle temperature of 210° C, speed/feed rate of 50 mm/min, grid as a structure/infill pattern and raster orientation of 0° are required.

The development of residual stresses in tools due to machining is a widely known fact and these residual stresses can often lead to unwanted modifications in tool life. Turning, tapering and threading are extensively used in various manufacturing processes and they are specially used for the machining of different types of Friction stir welding/ processing (FSW/FSP) tool pin profiles. FSP being a solid-state process undergoes high levels of plastic deformation and so tool pins having extreme values of residual stresses may pose a problem for longevity of tool life. In this research, turning, tapering, and threading operations were conducted to produce two types of FSW/FSP tool pin profiles namely taper cylindrical and taper threaded. H13 tool steel is extensively used to produce tools FSW/FSP and hence it was chosen. H13 tool steel workpiece with 110 mm length and 22 mm diameter was taken as the workpiece and machining operations were performed to produce FSW/FSP tool on CNC Lathe machine. The objective of the present study is to establish the values of residual stresses developed in both tool pin profiles by utilizing the PulsetecµX-360n portable stress analyzer setup. The results that are achieved are then compared for both the pin profiles – taper cylindrical and taper threaded. It was observed that sigma(x) and tau (xy) residual stresses, both are higher in the case of taper threaded pin, and tau (xy) value is significantly higher for taper threaded.

This research focuses on the use of Artificial Neural Network (ANN) for the prediction of the microhardness of friction stir processed aluminium based metal matrix composite (AA6061+Al2O3). Different specimens were obtained by using rotating speeds of 1100, 1210, 1320 and 1430 rpm and travelling speeds of 36, 48, 60, 72 mm/min. The microhardness value (HV) of the processed surface of each of the samples was measured and the data collected from the specimens was used as learning data for ANN. Higher rotational speed and lower transversal speeds resulted in higher hardness value since processing at higher tool rotational speed causes high material flow and good resistance to the tool pin profile. The increase of tool rotational speed also leads to the decrease of spindle torque due to ease of flow of material. A uniform increase in microhardness was observed up to 1320 RPM and a subsequent decrease on any further increments of tool rotational speed. Subsequently, the highest values of microhardness were observed with a square mandrel at 1320 RPM and 36 mm/min. The calculated results were satisfactorily compliant with the measured data and the ANN model was successful in predicting the microhardness.

Advancements in technology in the fields of satellite and aerospace systems and the need for smaller yet efficient designs have paved the way for further research into nano and pico-satellites. Smaller systems can prove to be more economical in investigating and measuring various parameters of the atmosphere in a localized area. This paper aims to demonstrate the design of one such system. A can-sized satellite (CanSat) has been designed with respect to the restrictions imposed by the CanSat Competition 2020. The design is developed in a way that allows it to be lightweight without compromising structural integrity. The manufacturing technique aimed to be used is 3D printing using Polylactic Acid (PLA) which allows for greater flexibility in customization and ease of fabrication. The application areas of the model satellite range from space exploration to weather forecasting.

Fabrication of glass fibre reinforced plastic was done using wet layup process and is discussed in the paper. The main purpose of the experiment was to identify the changes in the GFRP when subjected to various chemical resistance test and toughness test. GFRP was combined with different materials to form hybrid natural composite whose characteristics were studied and analysed. The results showed that GFRP had maximum chemical resistance in 5% Sodium hydroxide and minimum in 20% Sulphuric acid. From the Izod impact test, the maximum impact strength was found in unidirectional GFRP and minimum was found in orthogonal GFRP.

In the present work composite material is prepared by a combination of two or more constituent’s materials using squeeze casting process. Magnesium based metal matrix composites are casted using magnesium alloy reinforced with various volume fractions of silicon carbide particulates. A squeeze casting process has been employed under an inert atmosphere to produce magnesium matrix composites and this process leads to a complete wetting of silicon carbide particulates in the molten magnesium. Further, the synthesized magnesium based metal matrix composites are machined by computer numerically controlled lathe. Surface roughness and Metal Removal Rate of the composites are measured and their variation in performances are studied using orthogonal array, Also the mechanical behavior of the composites are determined and also evaluated by comparing the results with the unreinforced magnesium alloy.