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Lightweight materials with better resistance to sliding wear are prominent candidates for automobile brake drums, clutch pads and cylinder block applications to facilitate fuel economy. This attempt is reserved to cater to materials with higher tribological quality needs. Less dense foamy pumice stone particles were involved in three different percentages (5, 10, and 15 wt%) to reinforce lightweight AZ31 Mg alloy. A stir-assisted squeeze casting technique was pursued to process the composite and refine the grain structure. A phase detection, elemental mapping and microstructure study were done through X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and scanning electron microscopy (SEM), respectively. An experimental dry sliding wear scrutiny was administered using a pin-on-disc apparatus by considering: (i) ambient and elevated temperature environments and (ii) three different levels of loads. The results reveal a significant drop in wear loss and a frictional coefficient for 15% pumice-loaded composite than the base alloy. Post-wear examination acknowledges the fact that the ambient temperature wear is governed by adhesive-abrasive wear and high temperature is by abrasive wear mechanisms. Worn-out scrutiny authenticates the presence of oxide layers and their role in lubrication. A comparative study with previous works upholds the novel magnesium composite is the right candidate for the mentioned automobile applications.

The implementation of hard-facing alloy on the existing materials caters the need for high-performance surfaces in terms of wear and high temperatures. The present research explore the effect of Plasma Transferred Arc Welding (PTAW) parameters and powder composition on dilution, microstructure and hardness of the commonly used hard-facing alloy Ni–Cr–Si–B powder. The hard-facing alloy was deposited with three weight proportions of boron (2.5 %, 3 % and 3.5 %). The statistical-based Grey Relational Analysis (GRA) followed by a Machine Learning Algorithm (MLA) was implemented to identify the ideal parameters and degree of significance of each parameter and for the prediction of the responses. The dilution percentage, microstructure analysis, and phase detection were estimated through elemental analysis, Scanning electron Microscopy (SEM) and X-ray Diffraction Analysis (XRD) respectively. The experimental and modelling results revealed that 400 mm/min of scanning speed, 8 gm/min of powder delivery, 14 mm of stand-off distance, and 120 A of current were the optimal parameters along with 3.5 wt% of boron powder composition to yield a better dilution, microstructure and hardness.

ABSTRACTThe current study examines the effect of NaOH treatment on the hardness, inter-laminar shear strength (ILSS) and water absorption behavior of epoxy composites reinforced with banana pseudostem fibers. Using the hand-lay-up method, six distinct samples are created that are composed of layers of woven and short banana fibers in both a plain and hybrid form. Plain- treated woven composites reveal the highest hardness and ILLS properties followed by the hybrid and short fiber composites. The random orientation of the fiber structure in short fiber composites results in the largest moisture absorption; this behavior is further supported by elucidating the kinetic parameters and diffusion coefficient parameters. SEM analysis confirms the improved surface of the NaOH-treated composite material.

ABSTRACTNowadays, synthetic fiber composites are in decline because of their high initial cost and detrimental impact on the environment. The main aim of this work is to develop natural fiber composite materials that are made from moringa and bamboo fibers by using the hand lay-up method by maintaining a constant 40 vol.% of epoxy content. Both the natural composites were treated with NaOH and also compared with their hybrid composite. The mechanical properties, such as compression, hardness, impact, tensile, flexural properties were investigated. Additionally, thermo gravimetric analysis of composites was also carried out. The biggest boost in compressive strength was seen in bamboo with 60% volume, with improvements ranging from a pure resin value of 13.06 to 68.43% compared to moringa 60% and 30–30% moringa-bamboo. The maximum rise in impact strength was recorded by BM-30/30 at 21J. In addition to this, the highest hardness value was observed by moringa-reinforced composites (MM-60) and noted to be around 40.83 HV. Tensile and flexural properties of all the composites reveal improvement as compared with neat epoxy composites. Bamboo exhibits a considerable improvement in thermal stability as compared with other compositions. Scanning electron micrographs were used to analyze the structure-property correlations.

Abstract Recently, most service or product-oriented industries have been focusing on their activities to uphold the green and sustainable environment protocol owing to the increased environmental pollution. Concerning this issue, industries are now concentrating on developing recyclable or waste materials products. This research advocates developing and validating a banana fiber sandwich composite to promote the beneficial usage of bio-waste. The composite sandwich specimens were fabricated with resin-impregnated woven banana fiber mat as a skin, and the core was reinforced with three different weight percentages (5, 7.5 and 10%) of chopped banana fiber. The sandwich specimens were pressed into a three-point bending test to validate the structural integrity. The flexural characteristics like flexural strength and modulus were examined experimentally, whereas the key strength indices like flexural stiffness and core shear modulus were evaluated analytically. Post-fracture surfaces were studied through a scanning electron microscope to investigate the failure mechanism. The experimental and analytical results indicate that 10% banana fiber content in the sandwich core increases the flexural strength and flexural modulus to 225% and 147%, respectively, compared to the neat epoxy core. The numerical simulation was also performed through FEA to validate the experimental findings. The numerical results are in good concurrence with the experimental one.

Cardiovascular diseases, particularly coronary artery disease, pose big challenges to human life. Deployment of the stent is a preferable treatment for the above-mentioned disease. However, stents are usually made up of shape memory alloy called Nitinol. The poorer surface finish on the machined nitinol stents accelerates the migration of Nickel ions from the implanted nitinol stent, which is considered toxic and can lead to stenosis. The current study deals with controlling surface quality by minimising surface roughness and improving corrosion resistance. Femtosecond laser (fs-laser 10−15 s) micromachining was employed to machine the Nitinol surface to achieve sub-micron surface roughness. The Grey relational analysis (GRA)-coupled design of the experimental technique was implemented to determine optimal levels of four micromachining parameters (laser power, pulse frequency, scanning speed, and scanning pattern) varied at three levels to achieve minimum surface roughness and to maximise the volume ablation. The results show that to yield minimum surface roughness and maximum volume ablation, laser power and scanning speed are in a higher range. In contrast, the pulse frequency is lower, and the scanning pattern is in a zig-zag manner. ANOVA results manifest that scanning speed is the predominant factor in minimising surface roughness, followed by pulse frequency. Furthermore, the corrosion behaviour of the machined nitinol specimens was evaluated, and the results show that specimens with lower surface roughness had lower corrosion rates.

Fiber reinforced polymer (FRP) composite materials have huge demand in various fields due to their low weight and better mechanical qualities. Machining of FRP composite materials without damage is quite difficult using traditional machining systems owing to their intrinsic anisotropy, heterogeneity, and temperature sensitivity. Abrasive water jet machining (AWJM) is a known versatile technique to address the machining of FRP composite with minimal damage. However, kerf taper and delamination are the significant damages usually recorded in AWJM. The present work aims to minimize the above-said damages by applying a hybrid grey relational analysis (GRA)-principal component analysis (PCA) mathematical model. The glass and carbon fibers are used as reinforcements in the epoxy matrix. Nine experiments are conducted by considering hydraulic pressure, the mass flow of abrasive, standoff distance and transverse speed as machining parameters at three different levels each. The experimental and empirical results reveal that the mass flow of abrasive and hydraulic pressure are significant parameters to minimize the kerf damage, whereas the mass flow of abrasive and standoff distance are the parameters to reduce the delamination damage. The confirmation experiment based on the recommended optimized parameter records the reduction in delamination damage and kerf width damage to 33.9% and 11.72%, respectively. The adequacy and accuracy of the proposed mathematical model is being performed with the value of indicators R2 and adjR2, which are all closer to one.

In the current investigation, the mechanical properties of epoxy composites reinforced with banana pseudostem fibres, specifically focusing on tensile and impact behaviour, are investigated. The manufacturing process employed the meticulous hand-lay-up technique to fabricate six distinct samples. These samples included various combinations of short and woven banana fibres, treated and untreated, as well as a hybrid configuration involving layers of woven and short fibres. A fixed weight ratio of 60% fibres to 40% epoxy matrix was maintained for consistency. To ensure optimal material integrity, a careful application of resin and hardener in a 10 : 1 weight ratio was layered, with each addition of fibre followed by thorough rolling to eliminate any potential bubbles. The density and void fraction of the resulting composites were meticulously assessed to gauge the influence of this layering approach. Additionally, an X-ray diffraction (XRD) analysis was conducted to ascertain the impact of the chemical treatment on the cellulose content of the fibres. Our findings revealed that the tensile and impact properties were notably superior in the woven fibre composites. In particular, the chemically treated woven banana fibre epoxy composite displayed impressive values of 64.95 MPa for tensile strength and 24.37 KJ/m2 for impact strength. To gain deeper insights into the structure-property relationship, test specimens were analyzed using scanning electron micrographs. Lastly, comparative analysis by mapping the tensile properties from our present work with those from existing studies was carried out.

The present research investigates the wear characteristics of an epoxy composite reinforced with a novel Caesalpinia decapetala (CD) shell. The CD is available abundantly worldwide, especially in Ethiopia, particularly in East and West Oromia near West Harar. The composite specimens were processed in the open mould casting technique by varying the vol.% of CD in 10, 20, and 30. EDS is used to evaluate the important elements present in the CD. The density of composites increases with the increase in the content of CD, while the void content estimations reveal good control over the composite fabrication. The wear response of composites is investigated by varying the sliding distance and load and by maintaining a fixed velocity (5 m/s). At a 5 km slide distance and 50 N load, the 30 vol.% Caesalpinia decapetala composition depicts better wear resistance and friction coefficient than other compositions. Experimental results are used to envisage the ideal wear factors and to assess the influence of parameters over the two wear objectives, wear rate and CoF. The grey relational analysis- (GRA-) coupled artificial neural network (ANN) hybrid technique was employed for the prediction and validation. It has been observed that a trivial error of 0.49% amidst GRA and ANN estimation is observed.

The present research employs the statistical tool of Response surface methodology (RSM) to evaluate the machining characteristics of carbon nanotubes (CNTs) coated high-speed steel (HSS) tools. The methodology used for depositing carbon nanotubes was Plasma-Enhanced Chemical Vapor Deposition (PECVD). Cutting speed, thickness of cut, and feed rate were chosen as machining factors, and cutting forces, cutting tooltip temperature, tool wear, and surface roughness were included as machining responses. Three-level of cutting conditions were followed. The face-centered, Central Composite Design (CCD) was followed to conduct twenty number of experiments. The speed of cutting and rate of feed have been identified as the most influential variables over the responses considered, followed by the thickness of cut. The model reveals the optimized level of cutting parameters to achieve the required objectives. The confirmation experiments were also carried out to validate the acceptable degree of variations between the experimental results and the predicted one.

The development of aluminium composite with the inclusion of advanced materials is a continuous research process due to the increasing industrial demand for advanced hybrid materials. To cater for this need, this research work focuses on the development of Al 7075 alloy reinforced with TiB2 and graphene and on the evaluation of its strengthening mechanism. Two different modes of improving the strength of the hybrid composite have been followed; one is by the inclusion of graphene at three levels of 0.1, 0.2 and 0.3%, and another by the processing route, squeeze casting technique by compression of the molten hybrid composite slurry before casting. The microstructure and characterisation of the composite material are examined and analysed with the help of XRD, SEM, EDAX and chemical spectroscopy. A microstructure evaluation is employed to justify the homogenous dispersal and the existence of reinforced particles. A tensile test is conducted at room temperature and high temperature environments to assess the tensile strength. The research outcome affirms that a significant improvement in tensile and hardness has been noted in comparison with base alloy. The fracture-morphology results affirm the change in fracture mode from brittle to ductile when the tensile testing environment changes from room temperature to high temperature. Finally, the dispersion strengthening mechanism is validated with an empirical approach.

The emerging technique of micro electro mechanical systems throws a lot of challenging in the micro and nanoscale of machining. The present research explores the development of hybrid aluminium composite with hard particles boron carbide and silicon carbide in 10% volume fraction, and drilling of micro-holes using micro Electro Chemical Machining (µECM) process. The experiments were conducted based on Taguchi's design of experiments. The chief drilling parameters considered for electrochemical drilling were frequency, voltage, current, and electrolyte concentration. The machining duration and electrode wear were observed as the machining responses. After the experimental trials, the observed machining responses were transformed into equivalent Multi Response Performance Index (MRPI) through Grey Relational Approach (GRA) approach. This MRPI were further analysed through Principal Component Analysis (PCA) so as to determine the exact interaction effect of each parameter on the machining responses. The supply current and electrolyte concentration were found to impact the responses at a bigger level, but frequency and voltage were at the meagre level. The research declared the purposeful finding of optimized micro-drilling parameters of 30 Hz frequency, 8 V voltage, 16A current, and 0.4 mol of electrolyte concentration. The data presented in the articles are highly contributed to enhancing the micro-drilling process in terms of good process capability.

The present study evaluates the influence of nano MoS _2 particles on the wear properties of newly developed TiB _2 and Graphite reinforced Aluminium composite. Micro particles of MoS _2 are downsized into nano levels using a planetary ball mill. Three different compositions of specimens are fabricated through stir casting, with a constant 10% of weight of TiB _2 , graphite, and nano MoS _2 is kept at varying amounts of 10, 15, and 20%. The dry sliding wear tests are executed by following Taguchi’s design of experiment. The wear rate and coefficient of friction are considered as responses, whereas the normal load, sliding distance and the composition of MoS _2 are considered as the chief parameters with three levels. The hybridized Taguchi-Grey Relational -Principal Component Analysis mathematical model is implemented to study the effect of wear parameters and inclusion of MoS _2 on the wear behavior. Mathematical and experimental results explore the increasing nano MoS _2 content reduces the wear rate and coefficient of friction of composites. Analysis of variance results also acknowledge that nano MoS _2 content in the composite is a remarkable parameter to impact the tribological property. The hybrid statistical model results explore that the optimum parameter to yield better tribological property are 30 N normal load, 2 km sliding distance and 20% of MoS _2 . Worn surfaces are analyzed using scanning electron microscopy to picturize the wear mechanism concerning the varying content of reinforcement.

Modern aluminium composites reinforced with variety of hard particles become more usage in Industrial environment. But manufacturing of composites with homogenously distributed reinforcement becomes the challenge. To overcome this challenge, most of the Aluminium composite are undergone a secondary extrusion process. The data presented here are related to hot extrusion of round geometry to hexagonal section Al/B4C composite. Availability of data is extended to expose the optimal parameters of the process over the extrusion load and tensile strength of the extrudate. Ram speed, geometry of die profile, billet temperature and friction within the die and billet interface have been considered as chief process parameters which influence the extrusion load and strength of the product. Totally, nine experiments were conducted as per Taguchi's L9 orthogonal array to reach optimal parameters. Most influencing parameters with ranking significance have been arrived through ANOVA, MRPI and grey grade. Optimal parameters were compared with confirmation experiments and predicted one to justify the investigation Keywords: Composite material, Taguchi's technique, Grey grade, Tensile strength, Extrusion, Extrusion force

Effect of parameters affecting solid particle erosion of crumb rubber epoxy composite is investigated. Five important process parameters—impact velocity, impingement angle, standoff distance, erodent size, and crumb rubber content—are taken into consideration. Erosion rate and erosion efficiency are included as the chief objectives. The Taguchi coupled gray relational analysis type statistical model is implemented to study interaction, parameters’ effect on responses, and optimized parameters. ANOVA and regression model affirmed impingement angle and crumb rubber content play a significant role to minimize the erosion. Validity of the proposed model is justified with the standard probability plot and R2 value. A confirmation experiment conducted with A2B2C3D3E3 condition registers noticeable enhancement in GRG to the tune of 0.0893.

The effect of crump rubber on the dry sliding wear behavior of epoxy composites is investigated in the present study. Wear tests are carried out for three levels of crump rubber (10, 20, and 30 vol.%), normal applied load (30, 40, and 50 N), and sliding distance (1, 3, and 5 km). The wear behavior of crump rubber–epoxy composites is investigated against EN31 steel discs. The hybrid mathematical approach of Taguchi-coupled Grey Relational Analysis (GRA)—Principal Component Analysis (PCA) is used to examine the influence of crump rubber on the tribological response of composites. Mathematical and experimental results reveal that increasing crump rubber content reduces the wear rate of composites. Composites also show a significant decrease in specific wear values at higher applied loads. Furthermore, the coefficient of friction also shows a decreasing trend with an increase in crump rubber content, indicating the effectiveness of reinforcing crump rubber in a widely used epoxy matrix. Analysis of Variance (ANOVA) results also reveal that the crump rubber content in the composite is a significant parameter to influence the wear characteristic. The post-test temperature of discs increases with an increase in the applied load, while decreasing with an increase in filler loading. Worn surfaces are analyzed using scanning electron microscopy to understand structure–property correlations. Finally, existing studies available in the literature are compared with the wear data of the present study in the form of a property map.

Since the moisture present in the vegetables and fruits are initially more, they are endangered to spoil quickly. The ability of the desiccant materials to absorb moisture can be used for drying. By incorporating desiccants in the drying process, drying can also be carried out during no sunshine periods. The absorbed moisture can be desorbed by passing hot air stream through the desiccants. A cylindrical desiccant mould with varying diameters of concentric holes, comprising of vermiculite (20%), bentonite (60%), cement (10%) and calcium chloride (10%) has been prepared. The sizes of the concentric holes were made in three different diameters as 6, 12 and 18 mm. Different mass flow rates and temperatures were followed to conduct the experiment as per Box- Benhen design. The ANOVA analysis was performed to arrive the percentage of contribution of influence over the desorption. Various indicators including the percentage of error between measured and predicted responses were employed to uphold the accuracy of the proposed mathematical model. The extensive statistical study reveals that the 6 mm of hole diameter, 0.003 Kg m ^−2 s of mass flow rate and 60 °C temperature are the optimal parameters for the solid desiccant to regenerate effectively.

Physical contact between the moving parts of machines is inevitable in nature. The loss of dimensional stability due to wear is a great challenge in the industrial environment. To cater to this need, the development of advanced materials is in a continuous process. The present work focuses on evaluating the mechanical and tribological properties of the newly developed Al composite reinforced with hard particle TiB2 and two solid lubricants, graphite and nano MoS2. Three different compositions of specimens with constant weight % of TiB2 and graphite are maintained to 10 %. A planetary ball mill is employed to reduce the micro MoS2 to nano level, and their weight % of nano MoS2 is maintained in varying levels of 10, 15, and 20 %. The liquid processing method of the stir casting technique is followed to fabricate the hybrid composite specimens. The microstructural study confirms the homogeneous distribution of the particles, whereas XRD analysis confirms the presence of particles. The pin and disc dry sliding wear test is conducted to examine the wear rate and CoF. The wear test outcomes declare that the increased inclusion of nano MoS2 reduces the wear loss and CoF. Post wear analysis through SEM micrographs confirms the presence of a lubricant layer that regulates the change in wear mechanism concerning the load. The remarkable low CoF of 0.11 is recorded for rich reinforcement with minimum load. [ABSTRACT FROM AUTHOR]