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Near-net shape casting having complex geometry is manufactured through the sand casting process. However, day by day, the availability of natural or synthetic silica sand has been decreasing and increasing the production cost of sand casting components. Therefore, there is a need to look into low-cost and readily available alternative materials to substitute the commercial-grade silica sand for the sand mould casting process. The constituent of silica sand is primarily silica (SiO2), Al2O3, and Fe2O3. The major constituents of industrial wastes such as fly ash, blast furnace slag, ferrochrome slag, stone dust, and red mud have SiO2, Al2O3, and Fe2O3. Therefore, industrial wastes may be used individually or combined with silica sand at a different ratio to substitute the commercial-grade silica sand in green mould castings. Researchers and scientists have evaluated the suitability of industrial wastes and local riverbed sand as an alternative material for green sand mould castings. The present review summarizes the advantages and constraints of using industrial wastes and local riverbed sand as an alternative to green sand mould casting process.

The availability of silica sand for Indian foundry industries has been decreasing day by day. The present investigation evaluates the power plant fly ash (F-type) suitability as an alternative material to silica sand for Indian foundry industries. The sand mould properties such as permeability, hardness, compressive and shear strength, and compactibility are evaluated as per the standard (American Foundry Society (AFS)). The fly ash is added to silica sand at a different weight percentage (5 wt%, 10 wt%, 15 wt% and 20 wt%) and made the sand mould specimen. The physical and mechanical properties of fly ash blended silica sand mould is evaluated and compared with plain silica sand mould. The results revealed that up to 15 wt% of fly ash can be added to silica sand mould to meet the desired physical and mechanical properties of green sand mould castings. It is observed that the fusion point of fly ash is below 1350 °C and suitable for nonferrous sand casting. The utilization of power plant fly ash in green sand mould casting reduces environmental pollution and minimizes the scarcity of silica sand in Indian foundry industries.

Natural fiber-reinforced polymer (NFRP) composites are biodegradable materials than synthetic fiber such as glass and carbon fiber reinforced polymer composites. However, due to the lower mechanical properties of NFRP composites, application in structural components is limited. Therefore, the present investigation focuses on the effect of carbon and glass fiber hybridization with flax and Kenaf fiber on tribo-mechanical properties of the hybrid composites. Four types of hybrid composites (C2F3C2, C2K3C2, G2F3G2 and G2K3G2) and plain glass, carbon, flax and kenaf fiber reinforced polymer composites are fabricated by hand lay-up method. The results reveal that flax fiber hybridization with carbon fiber (C2F3C2) gives the best hybrid effect and improves its flexural strength (364.4 ± 15.0 MPa), modulus (24.7 ± 1.4GPa), and Izod impact strength (26.5 ± 2.4 kJ/m2). However, Kenaf fiber hybridization with glass fiber (G2K3G2) gives optimum flexural strength (335.6 ± 33.2 MPa), modulus (17.2 ± 0.9GPa), and Izod impact strength (80.2 ± 16.0 kJ/m2). Kenaf fiber reinforced polymer hybrid composites (G2K3G2) show the lowest abrasive specific wear rate (21.9 ± 0.9mm3/Nm) compared to other hybrid composites. Furthermore, the fractography analysis of hybrid composites is carried out using scanning electron microscopy to make possible structure–property co-relationship.

Researchers and scientists have observed that due to the low impact characteristics of natural fibre reinforced polymer composites, it has limited use in different structural applications. However,...

The present investigation focuses on the design and development of low-cost carbon and glass fiber-reinforced polymer hybrid composite with optimum flexural strength and modulus, Charpy impact strength, resistance to low-velocity impact, and abrasive wear. There are three hybrid composites ([C2G8], [C3G7], and [C4G6]) along with a plain glass ([G10]) and carbon ([C10]) fiber-reinforced polymer composites are fabricated using hand lay-up method. The results revealed that [C2G8] type hybrid composite possessed optimum flexural strength (394.35 MPa), resistance to low-velocity impact (92.42 J), Charpy impact strength (160 kJ/m2), and minimum specific wear rate (22.87 × 10–3 mm3/Nm) in comparison to other hybrid composites. The damaged area due to low- velocity impact was found to be least for [C2G8] type hybrid composite compared to other hybrid composites. Furthermore, fractography analysis was carried out by visual inspection and scanning electron microscopy to make possible structure–property co-relationship.

The present investigation focuses on developing cost-effective Carbon/Glass/Kevlar fiber-reinforced polymer hybrid composite laminates for achieving its synergistic effect on flexural and impact performance. It investigates the effect of stacking sequence induced by the use of different fiber types (Kevlar = K, glass = G, and carbon = C) on the flexural and impact performance of the composites. Five hybrid composites (labelled as A = [G2K3G2], B = [KG2CG2K], C = [CKGCGKC], D = [CGKCKGC], E = [CK2CK2C]) and three plain (i.e., non-hybrid) composites (F = [K]7, G = [G]7, H = [C]7) have been fabricated through manual pre-preg lay-up manufacturing techniques. The flexural strength and modulus, hardness, and Izod impact strength have been evaluated for the fabricated composites and compared. The results showed that the D-type hybrid composite achieves the maximum positive hybrid effect as compared to other hybrid composites, possesses a hardness of 59 BHN, a flexural strength of 380 MPa, and modulus of 36 GPa, and impact strength of 80 KJ/m2. The fracture surfaces of the hybrid composite specimen have been analysed using scanning electron microscopy, and compared against the properties achieved for enabling correlations. Furthermore, the cost-efficiency of the hybridization in terms of flexural strength/cost, modulus/cost, and impact strength/cost ratio were evaluated for potential engineering and design applications.

Green sand mold casting process is an ancient manufacturing process where the manufacturing cost is very low and can produce intricate shape casting for different industrial applications. In recent years, the sand casting foundries are shifted from western countries to India and other Asian countries due to easy availability of manpower and raw materials. However, in India silica sand availability is decreasing gradually due to high production rate of sand casting products and huge civil construction, leads to increase in the cost of production of sand casting products. The current investigation aims to study the effect of binder and moisture percentage on local river bed sand mould compactibility and shear strength. The sand mould cylindrical specimens are fabricated as per American Foundry Society (AFS) to determine shear strength of the mould. The result shows that the mould compactibility decreases and shear strength increases with the increase in binder percentage. The optimum sand mould compactibility 52% and shear strength 0.56 kg/cm2 are observed at 7% moisture and 14% bentonite. Furthermore, the compactibility and shear strength of river bed sand mould and commercially used pure silica sand mould are compared and found local river bed sand may be used as alternative silica sand in green sand mould casting.

Reinforcement of carbon fibers (CFs) causes significant improvement of thermal and mechanical properties of various polymers, and therefore application of carbon fiber reinforced polymer (CFRP) composites is increasing substantially in automotive, marine and aerospace industries. In the present work CF impregnated epoxy matrix composite was synthesized through hand lay-up technique. Specimens for different tests were cut from the composite lamina as per ASTM standards. The test specimens were cured at 140 °C for 2 h, 4 h and 6 h. Density, percentage of porosity, hardness, tensile strength, impact strength, rates of abrasive wear and specific wear of the cured CFRP sample were determined experimentally and compared with past research results from open literature. Though impact strength of the composite was low compared to the past results, its tensile strength was comparable with that of ASTM A36 steel.

Retention of mechanical and thermal properties of nano-Al2O3 embedded glass fiber reinforced polymer (GFRP) composites in marine environment is necessary and need to be evaluated to realize the full potential of the nanocomposites. The plain and nanocomposites were seawater aged in a temperature controlled seawater bath at 70 °C for a duration of 40 days. The results revealed that seawater aged plain and nanocomposites deteriorate their flexural strength, interlaminar shear strength and glass transition temperature. However, with the addition of 0.1 wt% of nano-Al2O3 particles into the plain GFRP composite, the flexural strength increased by 12%, interlaminar shear strength by 11% in dry condition and seawater diffusion coefficient was reduced by 17% as compared to plain GFRP composites. Nevertheless, the glass transition temperature of the nanocomposites was not improved in dry and seawater aged conditions significantly. The fractured surfaces of tested samples were investigated through FESEM to support the new findings.

Commercially available plywood has been used in doors, windows, interior decorations of hose and commercial complexes, containers for transportation of goods. Moisture absorbs by the plywood (W) and deteriorates its physical and mechanical properties leads to degradation of its durability and reliability of the laminates. Therefore, hybridization with synthetic glass (G) fiber is one of the solutions to avoid water absorption and improves its mechanical strength of the hybrid composites in hygrothermal environment. Therefore, the present investigation emphasizes the effect of glass fiber position in the hybrid composites on its mechanical and vibrational responses as compared to plain plywood laminates. There were three types of hybrid composites were considered for this investigation. It was observed that maximum impact strength of 5.325 J/m2 was found to be in GWG2WG type hybrid composite, maximum flexural strength and modulus was found to be in G2WG2 type of hybrid composite and maximum natural frequency of 52.515 Hz was found to be in WG4W hybrid composite. However, the overall mechanical and vibrational properties were improved for G2WG2 type hybrid composites as compared to others. Therefore, the presence of glass fiber in the outer surface of the hybrid composites is the better position to achieve desirable mechanical and vibrational properties of the hybrid composites as compared to other positions. This hybrid composite may be used as alternative materials for containers in goods transport sectors.

The difficulties of machining of fiber reinforced polymer composites by traditional methods have limited the widespread application of composite materials. In this article, the mechanical properties such as flexural strength was evaluated and abrasive jet machining was performed for plain glass (G), carbon(C) and hybrid composite ([CG2CG]S) in dry and seawater aged condition. The material removal rate (MRR), surface roughness (Ra) and depth of cut (DOC) were determined. The improvement of flexural properties of hybrid composites in comparison to plain glass fiber reinforced composite was observed. The MRR and DOC were seen to be increased with rise in operating pressure. The MRR and DOC were higher for seawater aged composite than in dry condition.

The short fork is made of 6082 Aluminium alloy and used in propeller shaft of small or mini trucks. The objective of the current investigation is to find the influence of t-6 heat treatment on the hardness of short fork (yoke). The effect of aging time on hardness and Microstructural changes is investigated. The test samples of the 6082-aluminum alloy were initially forged into the short fork at temperature 450°C and then solutionizing at 540°C for 15 min followed by water quenching. Furthermore, it was artificially aged at 190°C for 60-240 minutes. Rockwell hardness test was performed to find out the relationship between hardness and aging time. The optical microscope was used to investigate the Microstructural changes of the Aluminium alloy with different aging time. The result revealed that the change in grain size and microstructure during solutionizing heat treatment and artificial aging process are responsible for the change in hardness of the alloy. Aging at 190°C for 240 minutes gives the desired hardness of the component. These process parameters will be helpful to achieve maximum hardness of short fork and will be useful to other gorging industries.

Composites are playing significant role in material industries, which seek composites to be cost-effective and environment friendly materials. Natural fibre are new fibre which has some characters that can be useful for material industries .Flax and kenaf one of the many natural fibre which are light in weight and biodegradable in nature. However, the mechanical properties of natural fibre are lacking behind compare to synthetic fibre .Thus, assessment of mechanical properties of natural fibre is necessary to improve the structural or mechanical application by hybridization. In this study , three point bending (flexural) test , barcol hardness , vibration test and three body abrasive wear properties are evaluated .The hardness of carbon fibre is 76.6% more than flax fibre ,which make carbon fibre more brittle material . Flexural modulus of synthetic fibre is moderately higher than natural fibre .The wear rate is determine with sliding distance of 1000m and applied load of 25.5N when applied on specimen, the natural fibre has low wear rate which make it suitable in abrasive environment. The impact energy storage capacity of glass fibre is more than other fibers such as carbon, flex, kenaf fibre. Vibration frequency of natural fibre is comparatively similar to synthetic fibre, and carbon fibre has natural frequency 28.9% more than kenaf fibre. For structural application, having higher natural frequency helps in designing mechanical components. Future scope of natural fibre is by making hybrid composite with synthetic fibre which may be a new revolution to composite materials. This increases the degradation life and performance of composite.

Abrasive jet machining (AJM) is a non-conventional modern machining process which employs a high velocity mixture of a fluid (air or gas) with micro abrasive grains to impinge on the very hard and brittle target materials like glass, quartz, sapphire, and ceramics to cause material removal by impact erosion. This paper is focused on abrasive jet drilling of borosilicate glass material with different grades of hot zircon sand abrasive particles at various bed pressures of the compressed air to form the hot abrasive air jet, after passing through the fluidised bed abrasive jet machining (FB-AJM) setup. The effect of different machining parameters such as pressure (P), standoff distance (S), grain size (G), and temperature (T) on the material removal rate (MRR), surface roughness (Ra), and flaring diameter (FD) are studied and analysed by Box-Behnken method of response surface methodology (RSM). The SEM micrograph analysis of the machined glass surface is performed to show the plastic deformations at different planes of the work piece and also it is revealed that the embedment of abrasive particles on to the work material is reduced due to hot abrasive jet.

The rising demand for metal matrix composites (MMCs) in current trend has led to the advancement of hard-to-cut materials. Of all MMCs, Aluminium metal matrix composite owing to its exceptional properties as compared to that of other metals, has gained popularity among researchers. Thus in the present study, aluminium with particulate silicon carbide (SiCp) composite is used and aim to evaluate the comparative effect of process parameters such as pulse on time, pulse off time, and peak current on metal removal rate (MRR), tool wear rate (TWR) and surface roughness (SR) during Electrical discharge machining (EDM) on Al-SiC12% metal matrix composite with the use of nano particles mixed in the dielectric fluid and without the use of particles. The uses of powders have led to the increase in spark gap between the tool and the electrode. Here, nano powders are used for better efficiency. Experimental work is followed by Central composite design with various combinations of process parameters. Response surface methodology (RSM) is taken up for mathematical modelling and correlating the EDM parameters with responses. Analysis of variance (ANOVA) is used to analyse significance of the model. The SEM micro-graphs reveal the difference in either of the case during machining with and without nano powders in dielectric.

Glass fiber reinforced polymer matrix composites have enticed the researchers since last few decades, due to their excellent mechanical properties and wear resistance behaviour. In this paper woven roving E-glass fiber reinforced epoxy resin composite was prepared by hand lay-up method, followed by curing at 140 °C for 6 h. Density, porosity and different mechanical properties, such as hardness, tensile strength and impact strength were evaluated experimentally, and the test results were compared and validated with the experimental results of open literature. Three-body dry abrasion behaviour of the composite sample was also investigated.

In the world of manufacturing, achieving sustainability in machining process is of prime importance. The present known hazards of conventional flood cooling method via mineral oils have made us realize the need to eliminate this ongoing process to ensure safety to operator’s health as well as to pass on a better environment to upcoming generations. Ionic liquids (ILs) are one such class of lubricants that have the potential to replace the mineral oils in machining with their promising properties. The results performed in various works reviewed in this paper have proved ILs to be a potential additive aiding better performance in terms of cutting force, tool wear and surface roughness. Application of ILs + additives (Benzotriazole (BTA) and Tricresyl phosphate (TCP)) in high-speed machining will be newer concept and need to be investigated to study the machinability of hardened steel.

Natural fiber reinforced polymer composites have been used in different industries because of its high specific strength, modulus, cheaper and biodegradability. However, natural fiber reinforced polymer composites have lower mechanical properties and degrades its mechanical properties through seawater aging or moisture absorption than the composites having synthetic fiber. Therefore, the hybridization of natural fiber with synthetic fiber is needed to improve its mechanical properties in seawater aged condition. In this present investigation jute, bamboo and glass fiber is taken as the reinforcement medium for the preparation of the polymer hybrid composites. Three variety of hybrid composites such as [GJB]s,[GBJ]s,[JBG]s were considered for this investigation. The specimens were aged in seawater for 30days. It is found that [GBJ]s hybrid composite absorb more amount of seawater than the other two hybrid composites followed by degradation of its flexural strength by 42% and modulus by 33%. The [GBJ]s type hybrid composites shows lowest specific wear rate than the other two hybrid composites in dry condition and for seawater aged condition [JBG]s type hybrid composites shows minimum specific wear rate as compared to other hybrid composites

In the trending materials technology, nano composites are gaining importance due to enhanced mechanical, thermal and optical properties. Among various nanofillers used in fiber reinforced polymer nanocomposites, nanoclays have received several attractions among academia and researchers due to its high aspect ratio and characteristic exfoliation/intercalation properties. The stiffness of glass fibre reinforced polymer composites is not very high in comparison to carbon fibres. In the present work, an attempt has been made to enhance the stiffness and tribological properties of glass fibres by mixing nanoclays in the epoxy matrix. Hand lay up method was adopted to make ten layered glass fibre reinforced polymer hybrid composite. The weight percentage of nanoclay was 1%, 3%, 5%, and 7% to understand the behaviour of the hybrid composites. It was observed that 5% loading of nanoclay shows the optimum amount at which all the properties like hardness, impact strength, flexural strength and specific wear rate was increased. However, with further increase in nanoclays, all the above said properties were deteriorated. At 5% nanoclay content, hardness increased by 33.8%, impact strength by 74.8%, flexural strength and modulus by 37.5% and 37.67% respectively. Hence the above hybrid composite may be considered as a better composite for various structural and industrial applicationse.

Silicon carbide particulate (SiCp) impregnated Al 7075 metal matrix composites (MMCs) were developed following liquid metallurgy solidification route, and heat treated at T6 condition. Effect of heat treatment, SiCp content and its mean particle size on compressive strength, impact strength, flexural strength and maximum deflection during three point bend tests were investigated. Results showed that the compressive strength, impact strength and flexural strength improved due to heat treatment. Increase in compressive strength and impact strength of the MMCs with a reduction of their flexural strength was observed on increasing the reinforcement content and reducing their particle size.

Discontinuous silicon carbide particle (SiCp) impregnated aluminium matrix composites were developed following stir casting method and subjected to thermal treatment under T6 condition. Optical micrographs of the composite samples revealed homogeneous dispersion of reinforcements with some local agglomerations. However, heat treatment reduced the particle agglomeration up to a considerable amount. Particle agglomeration increased on increasing the SiCp content and on reducing their particle size. Further, increase of the reinforcement content caused an increase in density and porosity of the composites. Rapid increase of porosity was observed with combined influence of particle size reduction and increase in particle content in the composites.

With the advancement in material technology over ages, there has been growing needs among the human civilization for advanced systems with a combination of properties, which no single material can furnish. In this regard composites pose as a material of choice which utilizes the advantages of the constituent materials at the expense of their weaknesses. Out of the different types of composites known, polymeric materials filled with several inorganic, synthetic, and/or natural fibers offer a wide range of inherent characteristics in terms of heat resistance, mechanical and impact strength, stiffness, low electrical conductivity, and permeability to gases such as O2 and water vapor. They also possess added advantages of being very lightweight and resistant to a corrosive environment, due to which polymer composites find a place in many applications such as military and commercial aircraft, sporting equipment, structural, and automotive parts. Such unique property combinations emerge as a corollary to the specific arrangements between the polymer matrix and its reinforcements and their interactions; in particular the type of reinforcement. The fillers may be particulate or fibers, may be of micro scale or nanoscale. The literature revealed that microsized fillers mostly contain structural imperfections which reduce the interfacial interaction between the components. However, when the fillers are downsized to nanoscale, those imperfections are reduced and ultimate properties of the reinforced composites may be expected. In this chapter we have tried to add a flavor of polymer nanocomposites in application areas of aerospace and automotive sectors.

Natural fiber-reinforced polymer composites (NFRPC) offer numerous advantages over the widely used nonrenewable materials sources in terms of recyclability, lower pollutant and greenhouse gas emissions, and enhanced energy recovery. Also, these materials are relatively cheap and have low density, low machine wear, good thermal insulation, and acoustic properties, high flexural strength, and abundance in quantity. Utilizing the synergetic effect, currently, hybrid composites are fabricated through a combination of multiple interfacial additives to overcome certain drawbacks like high moisture absorbing property and poor wettability often noticed in NFRPCs. In this chapter, the synergistic effect of NFRPC obtained through hybridization technique with multiple natural fiber fillers, the effect of nanofillers and synthetic hybridization are discussed.

Hydrothermal Behavior of Fiber- and Nanomaterial-Reinforced Polymer Composites provides critical information regarding the in-service environmental damage and degradation studies of nano/fiber reinforced polymer (FRP) composites focusing on hydrothermal degradation. Covering hydrothermal properties of a wide range of polymer composites, the book is aimed at graduate students, researchers, and professionals in material engineering, composite materials, nanomaterials, and related fields.