Engineering Headway Vol. 22

Abstract: Additive manufacturing (AM) has gained significant attention as a promising technique for producing complex-shaped components, particularly in the aerospace and biomedical industries. However, post-processing steps, such as heat treatment, can significantly influence the mechanical properties of additively manufactured parts. This research investigates the effect of supertransus heat treatment on the compressive behavior of Ti-6Al-4V (ELI) alloy produced through additive manufacturing. The specimens were subjected to a series of heat treatment cycles, including solution treatment and aging above the β-transus temperature range. Compressive tests were conducted on as-received and heat-treated samples to evaluate their mechanical properties and deformation behavior. Microstructure characterization was performed using optical microscopy (OM) and scanning electron microscopy (SEM). The results revealed that the microstructure of the as-built material primarily consisted of columnar grains and acicular α' martensite. Significant variations in microstructure were observed in heat-treated samples, particularly with changes in the cooling rate. The microstructure changes closely correlated with the compressive properties of the heat-treated samples. The heat-treated samples showed a reduction in compressive strength compared to the as-received samples but exhibited improved elongation behavior. These findings contribute to the broader understanding of post-processing effects on the mechanical properties of additively manufactured materials, enabling the development of high-performance components for various applications.

Abstract: Fused deposition modeling (FDM) has several advantages, including design freedom, part customization, and ease of realizing complex geometries. However, there exist some challenges with the process; these include but are not limited to porosity, anisotropy, roughness, and material compatibility. This study is focussed on the additive manufacturing of polymer composites (short carbon fiber reinforced polyamide 6) through the process of FDM. Such 3D-printed parts are very lightweight and possess superior mechanical properties, which makes them a potential candidate for applications where a high strength-to-weight ratio is desired. The combination of FDM parameters, namely nozzle temperature, layer height, and flow rate, are studied in this work. The effect of variation in these parameters on the porosity and flexural strength is recorded following the Taguchi design of experiments. In calculating porosity, the weight difference between the printed part and the CAD part is used. For the flexural test, the standard three-point bending test is performed. The optimal combination of parametric settings is observed to be the same for minimum porosity and maximum flexural strength. Moreover, the flow rate is identified as a significant parameter for FDM printing of the composite material under study. The prints obtained at a raster angle 0˚/90˚ and on-edge orientation are observed to have better flexural strength than the prints at a raster angle ±45˚ and flat orientation.

Abstract: Auxetic structures have gained extensive popularity because of their unique mechanical properties such as negative Poisson’s ratio, high strength to weight ratio, energy absorption capabilities, high shear modulus and vibro-acoustic properties. These structures are widely used in automotive shock absorbers, crash box, fasteners, sound absorbers, air seat cushions, and biomedical applications. Over the last few years, additive manufacturing (AM) techniques are widely used for fabrication of these structures. conventional auxetic structures possess limited plateau stress and energy absorption. In order to overcome limitation of conventional auxetic structures, various researchers have proposed hybrid and hierarchical auxetic structures and investigated mechanical properties and energy absorption capacity. The present paper describes a detailed literature review on mechanical properties and energy absorption capacity of additively manufactured hybrid and hierarchical auxetic structures under static and dynamic loading conditions. Further, there is a need of conducting experimental study on these structures for improving mechanical properties such as strength, stiffness and energy absorption capacity. There is enough scope of designing and studying deformation behaviour of hybrid hierarchical structures for maximizing mechanical properties under different static and dynamic loading conditions for specific application.

Abstract: Over the past few years, the development in the field of Internet of Things technologies, Big Data, and artificial intelligence has helped industries to digitalize the shop floor machine and enable the real-time monitoring and storing of data in the cloud. Real-time monitoring of shop floor machines plays a crucial role in manufacturing industries to maintain their machines, reduce downtime, and increase operational efficiency. This study presents a cost-effective solution for real-time monitoring of shop floor machines using open-source technologies, including Raspberry Pi as an edge computing device, Node-RED as a Gateway, and ESP-32 as a microcontroller. The proposed solution demonstrates the potential to revolutionize machine monitoring in manufacturing environments, offering preventive maintenance, and optimizing operational efficiency. The system gathers information from PLC with NODE-RED and various sensors such as SCT-13, ZMPT101B, and MPU 6050, installed on the shop floor machine. These sensors collect real-time data that reflect the health, performance, and power consumption of machines. The real-time sensor data also storing in the cloud as well as a local database for further analysis. Our research bridges the gap between edge computing and cloud-based monitoring, offering practical benefits to manufacturing industries, widespread adoption of our approach promises more efficient processes and resource utilization.

Abstract: The innovation and development of new technologies have become more pertinent for the next level of improvement in an already established processes like iron ore sintering. New technique was required to deal with super fines in solid wastes recycling in an integrated steel plant through iron ore sintering for controlling sinter plant stack emissions, reducing solid fuel rate and improving sinter productivity. After experiments with several available techniques, a simpler but effective process was developed and implemented to produce micro pellets from solid wastes. The addition of produced micro pellets in sinter mix resulted in ~2.4% increase in net sinter production along with improved carbon efficiency of fine particles & lower stack emissions. This paper elaborates the journey of innovations in developing technologies which not only solved emission related issues but also improved productivity and carbon efficiency of existing processes by developing and collaborating with local start-up.