Search Results (4)

The additive manufacturing (AM) process is used for joining materials to make objects from 3D model data, usually layer upon layer, contrary to subtractive manufacturing methods. This technology plays a significant role in fabricating orthopedic implants, especially parts of hip implants (HI), such as femoral head, stem, neck, polyethylene linear, acetabular shell, and so on, using biomaterials. These biodegradable resources are those that can be utilized as tissue substitutes since they are accepted by live tissues. Here, the study is to examine the most preferable AM process and biomaterial used for making HI, including its manufacturing methods, compositions, types, advantages, and defects and cross-examining the limitations to bring some new technology in the future. Then we elaborate on the outlook of the most preferable material, followed by evaluating its biocompatibility, detailed application, and structural defects occurring while using it as an HI. Subsequently, the physical characteristics and design constraints are also reviewed in the paper. We assess the current stage of the topology optimization technique (TO) with respect to the characteristics of newly designed implants. The review concludes with future perspectives and directions for research. Full article

In recent years, many alloys as well as composites of aluminium were developed for enhanced material performance. AA 6061 is an aluminium alloy that has extensive applications due to its superior material characteristics. It is a popular choice of matrix for aluminium matrix composite (AMC) fabrication. This study provides a review on AA 6061 aluminium alloy matrix composites produced through the stir-casting process. It focusses on conventional stir-casting fabrication, process parameters, various reinforcements used, and the mechanical properties of the AA 6061 composites. Several research studies indicated that the stir-casting method is widely used and suitable for fabricating AA 6061 composites with reinforcements such as SiC, B₄C, Al₂O₃, TiC, as well as other inorganic, organic, hybrid, and nanomaterials. The majority of the studies showed that an increase in the reinforcement content enhanced the mechanical and tribological properties of the composites. Furthermore, hybrid composites showed better material properties than single reinforcement composites. The usage of industrial and agricultural residues in hybrid composites is also reported. Future studies could focus on the fabrication of AA 6061 nanocomposites through stir casting and their material characterisation, since they have great potential as advanced materials. Full article

Electrical discharge machining (EDM) is an advanced machining method which removes metal by a series of recurring electrical discharges between an electrode and a conductive workpiece, submerged in a dielectric fluid. Even though EDM techniques are widely used to cut hard materials, low efficiency and high tool wear remain remarkable challenges in this process. Various studies, such as mixing different powders to dielectric fluids, are progressing to improve their efficiency. This paper reviews advances in the powder-mixed EDM process. Furthermore, studies about various powders used for the process and its comparison are carried out. This review looks at the objectives of achieving a more efficient metal removal rate, reduction in tool wear, and improved surface quality of the powder-mixed EDM process. Moreover, this paper helps researchers select suitable powders which are exhibiting better results and identifying different aspects of powder-mixed dielectric fluid of EDM. Full article

The effects of exogenously applied Moringa oleifera leaf extract (MLE), nitrogen and potassium were studied on the productivity and quality of two cotton cultivars (CIM-573) and transgenic Bt cotton (CIM-598). The Randomized Complete Block Design (RCBD) factorial experiment was conducted at Bahauddin Zakariya University, Multan, Pakistan (30.2639 °N, 71.5101 °E; 123 m asl), during 2016 and 2017, with three replications. The analysis of variance revealed the significance of cotton cultivars and foliar applications for the majority of traits studied, in both years. The CIM-573 had superiority for most of the traits studied in 2016 and 2017 trials, while the CIM-598 cultivar had significantly higher record for chlorophyll content, seed cotton yield, mean boll weight, and seed index in 2016 and sympodial branches per plant in 2017. Foliar application of Moringa Leaf Extract (MLE) and synthetic fertilizers showed significant differences for the traits studied compared to the distilled water. Exogenous application of MLE has a positive effect on photosynthetic and enzymatic activities that improve the efficiency of nutrients that are utilized, thereby improving the growth, seed cotton yield and quality of cotton cultivars tested. All the interaction effects had a significant influence on the traits studied, except ginning percentage in 2016. The interaction between the conventional cotton cultivar (CIM 573) and exogenous application of MLE + nitrogen + potassium had significantly higher effect on plant height, cotton yield, staple length, fiber maturity, and fiber strength for the 2017 trial and was superior for the quality parameters in 2017. The interaction of the Bt cotton cultivar (CIM 598) and the foliar application of MLE + nitrogen + potassium had superiority in cotton yield, yield components and the quality parameters in the 2017 trial. Both the CIM 573 and CIM 598 cotton cultivars had consistent expressions for all quality traits studied, although they did fluctuate in their expression to these agronomic traits between the field trials of 2016 and 2017. Additive gene effects could be the explanation for the unstable effects of yield and the related traits in the different environmental conditions of the field trials in the two years. Our results suggest that the exogenous application of MLE alone and in combination with nitrogen and potassium could be used to improve the productivity and the quality of these cotton cultivars. The correlation coefficients indicate strong associations between the agronomic and quality traits, indicating that one or more yield parameters could be used as selection criteria to improve the productivity and quality of cotton. Full article