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The design and development of machine tools play a vital role in the current economic growth. It facilitates the reduction of manufacturing cost coping with a quickly changing business environment. During the design of the machine tool, the dynamic characteristics need to be calibrated for avoiding uncertainties. This paper investigates the design, dynamic characteristics, and development of a single screw conveyor machine which is used to blend waste plastic material with catalysts. The conveyor machine model is created based on the idea developed from filament extruder machine with Pro-E solid modelling software. Its multibody dynamic analysis was carried out for the selected operational requirements in the ADAMS View. It shows that when the conveyor screw operated above the velocity of 42 m/s, the deformation will occur at a maximum value of 4.23 mm. The rigid body dynamic was carried out in ANSYS to solve the performance forecasting problems at their design stage. The dynamic analysis results were suggested to improve the conveying machine and driving mechanisms design parameters. [ABSTRACT FROM AUTHOR]

In this research, microstructural events and mechanical behaviors in dissimilar friction stir welding (FSW) of aluminium (Al) alloy AA6082-AA7075 joints have been evaluated to apply aerospace, defense, and military sectors. FSW parametric effects have a more significant impact on the mechanical performances and microstructure of produced joints. FSW tool rotational speed, welding speed, and tool plunge speed were chosen to make the weld joints. The rotational tool speeds of 1600 rpm and 2300 rpm, welding speeds of 40 mm/min and 60 mm/min, and tool plunge speeds of 20 mm/min and 30 mm/min were set as the upper and lower limits. A constant axial force of 5 kN was maintained throughout the joint fabrication process. A taper pin-profiled tool was utilized to produce the butt welded joints. Mechanical properties of microhardness, tensile strength, yield strength, elongation, and bending strength of the joints were analyzed. The response of the stir zone microstructure to processing parameters was evaluated using optical microscopy (OM) and fractographic analysis of a tensile specimen shown by scanning electron microscope (SEM). The weld joints produced at 2300 rpm, tool traveling rate of 40 mm/min, and tool plunge speed of 30 mm/min showed the greatest tensile strength of the 191 MPa hardness of 145 Hv at the weld center and also the maximum bending strength of 114.23 N/mm2 was achieved. The lowest bending strength of 25.38 N/mm2 was obtained at 1600 rpm with 60 mm/min due to inappropriate mixing of the base metals and poor joint quality. Furthermore, this study revealed that a higher tool plunge speed facilitates the formation of equiaxed grains in the thermomechanically affected zone (TMAZ) on the advancing side (AS). Additionally, the increment in tool rotational speed significantly improved the tensile strength, weld joint quality, and joint efficiency. [ABSTRACT FROM AUTHOR]

The thermal behavior of the biodegradable Calotropis procera (CP) particle-reinforced polylactic acid (PLA) biocomposites was investigated. The injection molding process was used to make the composites, and the CP particle weight percentage was varied during the process (0%, 5%, 10%, 15%, and 20%). The melt flow index, heat deflection temperature, Vicat softening point, and the thermal properties of the composites were determined using dynamic mechanical testing. The results were analyzed and compared to the thermal properties of the neat PLA. The results revealed the increase in thermal stability of the PLA due to the addition of CP particles. The CP particles aided in the restriction of polymer mobility, which elevated the glass transition temperature of the composite. Incorporating CP particles in the PLA can increase the PLA/CP composite utilization in heat dissipation applications. [ABSTRACT FROM AUTHOR]