Aerospace alloys with reduced wall thickness but possessing higher hardness, good tensile strength and reasonable corrosion resistance are essential in manufacturing of structures such as fuselage. In this work, friction stir welding has been carried out on such an aerospace aluminum alloy AA8090 T87 which contains 2.3% lithium. Tool rotational speed of 900 rpm and traverse speeds of 90 mm/min., 110 mm/min. are the welding parameters. Hardness analysis, surface roughness analysis and corrosion analysis are conducted to analyze the suitability of the joint for the intended application. The samples were corrosion tested in acid alkali solution and they resulted in the formation of pits of varying levels which indicate the extent of surface degradation. Hardness of the samples was measured after corrosion analysis to observe the changes. The analysis suggests that the change in tool traverse speed transformed the corrosion behavior of the joint and affected both the hardness and surface roughness which mitigated the quality of the joint.

In this study, the primary goal is to utilize the biological waste of water hyacinth (Eihhornia crassipes) plant fiber–reinforced polymer composite materials for commercial applications, especially for lightweight materials aspects. In this work, the physical, mechanical (tensile, flexural, and impact), thermal, and morphological properties of water hyacinth natural fiber composite samples are investigated. We strongly believe that only a minimum amount of work has to be done to this water hyacinth fiber composite oriented. Especially all the previous literature reported the hyacinth fibers are extracted from the retting process and manual method. But, in this work, hyacinth fibers are extracted from the new novel mechanical way of the extraction process. From the results of chemical analysis, water hyacinth fiber contains a very high 62.15% cellulose content and a minimum amount (14.82%) of hemicellulose content. The crystallinity index of water hyacinth fiber composite is 54.82%. The surface of the hyacinth composite is examined with the help of a scanning electron microscope. The thermal degradation of hyacinth fiber composite is measured with the help of the thermogravimetric analysis method. Based on the final experimental results, the water hyacinth natural fiber composite is the better alternative for other traditional fiber composites and it is strongly recommended for lightweight material applications.

In this investigation, naturally woven coconut sheath, a new type of reinforcement was used. The composite was fabricated using compression molding machine. The mechanical properties like tensile, flexural and impact strengths were studied according to the ASTM standards. For comparison, conventionally used glass fiber-reinforced composites were also fabricated and tested. In all the testing, the coconut sheath-reinforced polyester composite showed enhanced results. For further improvement in the properties, chemical modification such as silane treatment was given to the fibers. As expected, the mechanical properties of coconut sheath-reinforced composites were improved.

In this work, naturally woven coconut sheath, a new type of reinforcement was used. Composite Laminates were prepared in a compression molding press. Tensile, flexural and impact tests were conducted as per ASTM standards, and results were compared with the glass fibre composite. Fractured specimens were analyzed with the help of scanning electron microscope images. Enhancements in mechanical properties were found with the new reinforcement. And the coconut sheath was found to be a suitable material that can reduce the utilization of non-decomposed glass fibres for polymer composite reinforcements.