Papers by Keyword: Mechanical Property

Abstract: In this study, the influence of operating parameters on the relative density and microhardness property of a septenary equiatomic Ti-Al-Cr-Nb-Ni-Cu-Co high entropy alloy developed via spark plasma sintering (SPS) process was investigated at constant heating rate (100 °C/min), dwell time (5 min), pressure (50 MPa). Using response surface methodology (RSM) on the sintering temperature (ST) and milling time (MT) as the process variable parameters, a predictive model was established. The design of experiment approach was employed to minimize numbers of runs of experiment, which invariably eliminates trial by error associated with traditional experimental methods. MT and ST were taken as the variables towards the development of the design model. The optimum operating parameters were predicted using the user-defined design (UDD) under RSM and the result was validated through experiments. Observation from the results shows that MT and ST play a significant role in achieving high densification, which translates to high hardness. At 900 °C ST and MT of 10 hours, the highest hardness value of 580.1 HV, densification of 99.98%, and percentage porosity of 0.02% were recorded.

Abstract: Fibre reinforced polymer composites are employed instead of metal and wood because they are stronger, more lightweight, have a favourable strength to weight ratio, and are noncorrosive. In the current research, sisal, carbon fibre, and industrial waste tea leaf fibre (WTLF) reinforced hybrid epoxy composites are being examined for their chemical, mechanical and acoustical properties with experimental study. The sisal and WTLF were chemically treated with 5% sodium hydroxide (NaOH) solution. By modifying the weight percentage of sisal and WTLF with a structure of 40 weight percent fibre and 60 weight percent matrix, five different compositions of natural fibre reinforced hybrid composites were fabricated using an automatic compression moulding technique. As per the ASTM standard the manufactured hybrid composites are tested for mechanical, chemical and acoustic characteristics. According to the experimental findings, sisal fibre with a 25 wt% and WTLF with a 5 wt% demonstrated superior mechanical properties, while these materials also demonstrated an excellent acoustic absorption coefficient (AAC) of 0.62 between the frequency range of 2000 to 6300 Hz. The morphology of failure samples revealed the matrix micro crack, void formation, fiber pullout and layers of fractured fibers which are being examined using Scanning Electron Microscopy (SEM). The superior bonding between fibre and matrix was seen in the FTIR study of 5% alkali treated composites.

Abstract: The construction industry continually strives to enhance sustainability and reduce environmental impact. Developing innovative concrete materials that utilize recycled aggregates and alternative cementitious binders has gained significant attention in this context. This abstract presents a study on developing ultra-high-performance geopolymer concrete (UHPGC) by replacing fine aggregates with recycled materials. This research aims to develop UHPGC by incorporating recycled fine aggregate waste (RFAW) as a partial replacement for fine aggregate. Four different concrete mixes were prepared and tested to evaluate RFAW's influence on the performance of UHPGC, considering replacements of up to 30% of fine aggregate. The study examined the fresh properties and mechanical characteristics of the resulting material. The experimental outcomes demonstrated that adding RFAW enhanced the workability of fresh concrete, making it more easily manageable. However, the mechanical properties of the hardened concrete were slightly affected to some extent. Specifically, the compressive strength decreased from 119 MPa to 103 MPa when 30% RAW was added. Conversely, with lower replacement percentages of 10% and 20%, the concrete exhibited no reduction in strength compared to the 30% replacement levels. This reduction in strength could be attributed to a weaker bond between the geopolymer gel and the recycled fine aggregate particles. Additionally, it was observed that as the proportion of RFAW increased, the water absorption of the UHPGC also increased. This indicates that the concrete had a higher tendency to absorb moisture. Nevertheless, the findings suggest that RFAW waste could be a viable resource for producing environmentally friendly UHPGC with improved physical, mechanical, and durability properties with appropriate optimization. The outcomes of this study can promote sustainable construction practices by reducing the reliance on virgin materials and promoting the circular economy within the civil engineering industry.

Abstract: The key drivers of the growing interest in the recovery of local materials, particularly land and waste plants, are low-cost building materials, thermal comfort, decreased energy consumption, and decreased carbon dioxide polluting emissions. This work's primary objective is to test a bio-sourced composite material that takes the form of a block of unfinished soil that has been stabilized with cement and blended with wheat straw. This study is being done with the objective of examining the impact of this fiber at different weight percentages (0, 2, 3%, and 4%) on the mechanical behavior, durability, and thermophysical properties of the produced blocks. The results obtained indicated an increase in thermal conductivity, from 2.75 W/mK for the blocks without wheat straw fiber to 0.398 W/mK for those getting 4% of the wheat straw fiber, signifying an improvement in thermal insulation. While retaining the low performance threshold required by the earth construction standard, this improvement was accompanied by an average decrease in mechanical performance.

Abstract: Towards the sustainable development goals in the built environment, the use of waste and recycled sources has been attaining great interest among researchers and policy-makers, especially in concrete as the most used construction material. Excess use of natural aggregates, as one of the main components of concrete, causes the depletion of natural resources and the associated environmental problems, thus, the use of artificial and recycled aggregates is of great importance. In this regard, the production of lightweight artificial aggregates from industrial and hazardous wastes may be a promising solution that not only mitigates the depletion of natural resources but also stabilize those kinds of wastes. This study aimed to investigate the production of concrete with recycled aggregates from industrial wastes, mainly municipal solid waste incineration fly ash (MSWI-FA). To this end, different kinds of mix designs to manufacture the aggregates were developed based on MSWI-FA, ground granulated blast furnace slag (GGBFS), marble sludge (MS), and cement. The concrete samples containing different artificial aggregates, as well as recycled polyethylene terephthalate (PET) in the sand form, were produced and the properties, including compressive strength and thermal insulation, were evaluated. The obtained results of the lightweight concrete demonstrated enhanced thermal property (up to 30%), but at least 30% lower resistance with respect to the normal concrete produced from the natural aggregate.

Abstract: Aluminium alloy 2024 is widely used in the manufacturing of aircraft components such as skin panels for the wing. Generally, the aluminium alloy 2024 is delivered as cold work condition i.e., 2024 T3. However, the aluminium alloy 2024 T3 does not meet the standard for aircraft wing skin. Therefore, further treatments such as cladding and heat treatment are carried out to improve its quality. Cladding was introduced to the 2024 T3 alloy at 495 °C using commercial purity aluminium. Subsequently, T42 heat treatment was introduced to the 2024 T3 alloy at 500 °C for 40 minutes, then followed by quenching and natural aging for 96 hours, yielding 2024 T42 aluminium alloy with cladding (T42 Clad). 2024 T42 aluminium alloy without cladding (T42 Bare) was also obtained by T42 heat treatment of 2024 T3. The effect of cladding and natural aging on mechanical properties is investigated by tensile test and hardness test. Conductivity meter was used to determine the electrical conductivity. Intergranular corrosion test and stress corrosion crack test were performed to investigate the effect of cladding and natural aging on corrosion resistance. Results indicate that the solution treatment and natural aging improve corrosion resistance, mechanical properties, but reduce electrical conductivity values. Cladding gives higher electrical conductivity value and elongation. Both natural aging and cladding treatment provide appropriate aluminium alloy for aircraft wing skins.

Abstract: The filler materials are supported alongside natural fiber in the composite to work on the quality and property of the part materials given the prerequisites and their applications. In this paper, the mixture composite was created with Hemp/Carbon fiber. Different wt% (15%,20%,25%) of Hemp fiber and filler materials were utilized as support. The Hemp fiber was surface treated with 5% of KMnO4. The created hybrid fiber composites were performed with different mechanical properties concentrated on like tensile, bending, impact, and Brinell hardness this multitude of tests were proceeded according to ASTM guidelines. From the mechanical property study, 25 wt% Hemp fiber cross breed composite hold great mechanical properties contrasted with any remaining wt% created half breed composite. keywords:- hybrid composite, surface treatment, mechanical property, fillers.

Abstract: The natural filler material is reinforced along with natural fibers in the composite to improve the quality and property of the component materials based on the requirements and its applications. In this paper, the hybrid composite was developed with Hemp/ Basalt fiber. Various wt% (15%,20%,25%) of Hemp fiber and filler materials were used as reinforcement. The Hemp fiber was surface treated with 5% of KMnO4. The developed hybrid natural fiber composites were performed with various mechanical properties studies like tensile, bending, impact, and Brinell hardness all these tests were performed as per ASTM standards. From the mechanical property study, 25 wt% Hemp fiber hybrid composite hold good mechanical properties compared to all other wt% developed hybrid composite.

Abstract: Copper matrix composites (CMCs) are known to be lightweight and possess competent mechanical properties, hence is highly suitable for a broad range of advanced applications. Its significance in aerospace, marine, and structural domains make it worthwhile to be investigatedfor low-cost manufacturing and selection of appropriate reinforcements. A comprehensive understanding of CMCs in terms of its fabrication methodologies and the diverse properties achievable through the incorporation of discrete reinforcement materials are essential to beexplored. Given, this manuscript evaluates the distinct methodologies for the preparation of CMCs through various fabrication routes. Besides, the substantial improvement/variation in properties such as mechanical (strength, toughness, hardness and creep), metallurgical (microstructure, grain size and grain boundaries), thermal properties (thermal conductivity, coefficient of thermal expansion) and tribological properties (friction, wear) through the incorporation of reinforcements (additives/filler materials/adhesives) of CMCs also is brought under detailed discussion.

Abstract: The Friction Stir Welding process has become very popular because it produces good welds with low defects and distortion. However, FSW in thick aluminium alloy plate joints such as those found in applications in the transportation industry such as automotive, rail, shipbuilding, and aircraft is more complex and challenging. Double-sided FSW has challenges to be developed and applied in the transportation industry. This study investigates the effect of different tool rotational speeds on the double-sided FSW of Aluminium Alloy 6061-T6 thick plate. The ratios of the tool speed differences studied were 1:1, 1:1.3, and 1:1.6. Tensile strength, hardness, microstructure evolution, and fracture morphology were studied in this study. The investigation results concluded that an efficient and reliable double-sided FSW joint was achieved at joints with a tool rotational speed difference ratio of 1:1.