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The existing work deals with the development of Al-Si-Mg-Ni hypoeutectic alloys and to investigate the impact of solutionising time on their morphology and how these alloys behave mechanically. Al, Si, Mg, Ni of required weight percentages were melted into a clay graphite crucible and the mixture was poured into a permanent mould from which cast rods of o32 mm ×156 mm in length were obtained. The cast rods were solutionised at 538 °C for 2, 4, 6, 8 and 10 h, respectively. Further, the alloys were then quenched into 30 °C water and subsequently aged at 155 °C for 12 h. It is perceived from the investigation that, as the solutionising time increases, a refinement in the grain of the developed alloy occurs and the hardness and tensile properties were seen increasing. Moreover, ductility was found to be low for the alloy solutionised at 10 h as compared to the LM25 alloy. The scanning electron images of the fractured surface revealed that the increase of solutionising time from 2 to 10 h led to a much smaller extent of the observance of dimples on the fractograph. Furthermore, the fractured surface of the alloy solutionised for 10 h depicted the presence of micro-voids, which confirms the ceasing of ductile behaviour because of longer solutionising time.

The present article reviews the development of cast aluminium alloy with highlights on improvement in the morphological, mechanical, tribological, and ageing properties of Sr modified Al–Si and Al–Si–Mg alloys. Aluminium and its alloys find application in the automobile and aviation industries. The main objective of utilizing aluminium alloys for structural application, manufacturing of pistons and engine block for automobile industries is its lightweight and low density. However, the low hardness of these alloys results in a high wear rate. The main factor that affects the properties of aluminium alloys is its microstructure, morphological behaviour, size of the grain and phase distribution. The morphological modification for these alloys is done through different processing techniques like casting, heat treatment, solutionising, and alloying element addition which augments the mechanical, corrosion, and tribological behaviour of these alloys. Of the alloying element additions Sr has proved to a very effective modifier for the alloy, and hence the method of modification was studied in detail. The unwanted effects especially porosity, being one of the main factors for failure of components, were investigated and methods to reduce it according to many researchers were included. Reinforcing the aluminium matrix with ceramic particles and surface modification also enhances the properties of aluminium alloys. The current article reviews the recent techniques to augment the microstructure, value of hardness, tensile properties, tribological properties, and corrosion behaviour of cast Al–Si and Al–Si–Mg alloys by the addition of strontium. Moreover, this review also focuses on the future scope of these aluminium alloys for structural application in automobile and lightweight industries.

The current work is focused to ascertain the impact on the mechanical and morphological characteristics of hypoeutectic alloy Al–Ni with a range of solution treatment temperatures. Al, Ni, Si, and Mg of necessary weight percentages were melted in a crucible (make–clay graphite) and were cast. The cast alloys were then solutionised for 8 h from 450 to 550 °C, quenched and was aged for 12 h at 170 °C. The fractography, intermediate phase and the elementary composition of alloy was determined. It was observed from the investigation that a rise in solutionising temperature caused grain refinement in the developed hypoeutectic alloys. A surge in the value of hardness was observed with respect to the rise in solutionising temperature. It was also noticed from the analysis that the value of tensile strength, yield strength, ductility and impact resistance of the hypoeutectic alloys enhanced with temperature rise from 480 to 510 °C and then declined from 510 to 550 °C.

In the present study, the mechanical performance of age-hardened A356/TiC was investigated. 10 wt% of TiC of 35 µm was added into the melt and using liquid metallurgy route the composite rods were fabricated. The developed hypoeutectic composite was solutionised at 525 °C for 12 h, water quenched and aged at 155 °C for 3 h. Microstructure and hardness of the developed hypoeutectic composites were studied. It was perceived that in the heat-treated composites the undissolved precipitates form an intermediate phase which increases mechanical properties. It was noted from the investigation that the value of hardness was found to increase from the base alloy to the heat-treated alloy by 55%

The current research deals with the effect of solutionising temperature on the morphological behavior, hardness and tensile strength of Al-6.6Si-0.3Mg-3Ni alloys. In this work, the solutionising temperature was varied from 450 °C to 480 °C. The chemical composition of all cast samples was identified by using Arc Spectroscopy. The hardness of the cast samples was determined using the Vickers Hardness test. It was observed from the present investigation that, as solutionisation temperature increases, there observed a refinement in the gains of eutectic silicon crystals which enhanced the hardness and tensile strength values. The value of hardness and tensile strength was found to increase as the solutionized temperature increased. The heat-treated alloys under this investigation possessed superior hardness as compared to the LM25/A356 and as-cast alloy.

In this study, vertical centrifugal casting process is used for the fabrication of functionally graded A390 alloy hollow cylinder and Mg & Sr-included A390 alloy hollow cylinder. The commercial CFD software FLOW3D™ is used to obtain the optimum rotational speed for making an optimized hollow cylinder in a vertical centrifugal casting machine. The optimum rotational speed obtained is 1300 rpm. This rotational speed is used in the experiments to obtain hollow cylinders of optimized thickness for (a) A390 alloy (b) by adding various weight percentages of Mg and Sr in A390 alloy. The optical microstructures obtained at various radial locations are presented for centrifugally cast A390 alloy. The effect of individual addition of Mg & Sr into A390 alloy on the microstructures at various locations along the radial direction of centrifugally cast cylinder is discussed in detail.

The current study deals with the development of a hybrid metal matrix composite and studies their wear characteristics. Suitable wt - % of Al2O3/B4C was reinforced into Al-Si-Mg alloy and the composites were fabricated using liquid metallurgy route. The developed composites were analyzed for their wear behavior by using a wear testing apparatus. Three process parameters including applied load, sliding distance, and velocity were chosen for carrying out the wear experiments. The influence of the reinforcement on wear rate was investigated through response surface methodology methods. The formulation of the regression equation was done and the effect of each experimental parameter was studied. Results from the investigation illustrate that the wear rate was found to decrease and then increase with the increasing wt-% of reinforcement and the wear rate was found to increase with an increase in the sliding distance but the wear rate was found to decrease with an increase in the sliding velocity. The worn-out surface of the hybrid composite was characterized using SEM.

An investigation was conducted to evaluate the stress corrosion cracking resistance of copper based alloys. Cu, Ni, Sn of appropriate weight percentage were melted in a graphite crucible in an electric furnace under the argon atmosphere. The obtained specimens were solutionised and aged as per standards. The heat treated samples were subjected for microstructural evaluation and stress corrosion cracking test as per ASTM standard. In the microstructural analysis it was observed that the dendritic structure was completely vanished when the specimen was subjected to solutionising and aging. The stress corrosion cracking (SCC) was predominant in the regular bronze due to the formation of oxide layers according to the passive film rupture theory. But in the case of spinodal alloys only internal cracks were observed. These observed cracks were due to the pits and burrs present in the alloy

The current research work includes analysis of the impact of reinforcements B4C /SiC, on the mechanical Properties of Al-6.6Si-0.4Mg alloy. The reinforcement content was varied between 5- wt% and 10- wt% respectively. The mechanical properties- percentage elongation, hardness, tensile and yield strength were observed for varying weight percentage of reinforcement content and compared. The micrographs of the cast specimens were distinguished under an optical microscope and a scanning electron microscope and it was noticed that as the weight percentage of the added reinforcement content increased there was a subsequent transition from learner to finer distribution. Mechanical properties – hardness, tensile and yield strength displayed a similar trend of improvement in corresponding properties with a subsequent increase in the reinforcement wt-%. However, in the case of percentage elongation, there was a decrease in property with a corresponding increase in reinforcement.

Aluminium alloys have found application in many areas like automobile, aerospace and in fighter jets. The main problem for these alloys are the lack of mechanical properties and wear properties. These mechanical properties have huge effect from the microstructure. For analyzing the performance of the aluminium alloys, a study is carried out to examine the effect of cobalt addition on the hypoeutectic aluminium alloy microstructure. Pure cobalt of varying weight % were added into a clay- graphite crucible containing Al ingot. The melting was conducted by using an electric arc furnace at a temperature of 850°C±20°C and were poured into a permanent mould to obtain cast specimens. Solutionisation and aging were performed at a temperature of 525°C for 12hrs and 155°C for 1, 2,3,4,5 hrs.. The hardness of the developed alloy was found to increase with an increase in the Co addition. The UTS and YS was found to be increased with an increase in the addition of cobalt and the ductility was found to reduce with increase in the cobalt percentage.

The objective of this research is to fabricate a ternary alloy (Cu–Sn–Ti), incorporating titanium into bronze with varying weight percentage of titanium (0.5 wt%, 1 wt%) to investigate its impact on microstructural and mechanical properties and wear behavior and to collate these results with those of conventional bronze (Cu–6Sn). The microstructure of the alloys was observed using a metallurgical microscope, and results exhibit a finer grain refinement in the dendritic structure, which causes an improvement in mechanical properties. The mechanical properties were tested (tensile strength, hardness), and they showed an increment in values corresponding to the increase in the weight percentage of titanium. However, owing to the formation of an inclusion (blowhole), there was a reduction in the tensile strength for Cu–6Sn.0.5Ti. The wear analysis was also carried out using a pin-on-disk tribometer with selected parameters of load (10–30 N), sliding distance (1000 m) and sliding velocity (1–3 m/s), and it was noted that there was an increase in the wear rate with an increase in load and distance for all combinations of parameters. There was also an improvement in the wear resistance with an increase in the weight percentage of Ti, in comparison with the conventional base alloy.

Bronze, an industrially relevant material, is always at a constant need for improvement in its properties. It should possess superior hardness, wear resistance and high tensile properties. The microstructure of the composite was characterized by using an optical microscope. The mechanical and tribological tests were carried out on the developed composite samples as per ASTM standards. It was observed that the hardness of the developed bronze composite increases with an increase in the reinforcement addition. The tensile properties were found to improve with addition of reinforcement particles into bronze matrix but, there observed a decrease in the ductility of the composite as compared to the regular bronze alloy. The wear rate of the developed composite was found to be low as compared to that of the regular bronze alloy

The present research includes the analysis of mechanical properties of A356/ hybrid metal matrix composite. The mechanical behaviour - hardness, ductility, tensile and yield strength were studied. Reinforcement of these composite specimens were with a weight percentage of (wt - %) 10%, 20% and 30%. The microstructure of these specimens at different wt - % of reinforcements were viewed under an optical metallurgical microscope. It was observed that at 30 wt - % of reinforcement addition, there was a finer distribution of reinforcement particles and as the wt - % decreased, much leaner distribution was observed. The hardness test was carried out using a Vickers Hardness Tester. From the experiment it was noted that with an increase in the amount wt - % of reinforcement, there is a subsequent increment in the mechanical properties except in the case of percentage elongation, which was observed to decrease with an increase in the reinforcement content.

The article reviews the progress made on bronze alloys processed through various casting techniques, and focuses on enhancements in the microstructural characteristics, hardness, tensile properties, and tribological behaviour of Cu-Sn and Cu-Sn-Ti alloys. Copper and its alloys have found several applications in the fields of automobiles, marine and machine tools specifically for propellers in submarines, bearings, and bushings. It has also been reported that bronze alloys are especially used as an anti-wear and friction-reducing material to make high performance bearings for roller cone cock bits and warships for defence purposes. In these applications, properties like tensile strength, yield strength, fatigue strength, elongation, hardness, impact strength, wear resistance, and corrosion resistance are very important; however, these bronze alloys possess only moderate hardness, which results in low wear resistance, thereby limiting the application of these alloys in the automobile industry. The major factor that influences the properties of bronze alloys is the microstructure. Morphological changes in these bronze alloys are achieved through different manufacturing techniques, such as casting, heat treatment, and alloy addition, which enhance the mechanical, tribological, and corrosion characteristics. Alloying of Ti to cast Cu-Sn is very effective in changing the microstructure of bronze alloys. Reinforcing the bronze matrix with several ceramic particles and surface modifications also improves the properties of bronze alloys. The present article reviews the techniques involved in changing the microstructure and enhancing the mechanical and tribological behaviours of cast Cu-Sn and Cu-Sn-Ti alloys. Moreover, this article also reviews the industrial applications and future scope of these cast alloys in the automobile and marine industries.

The present research deals with the fabrication of Al–Si–Mg-Sr alloy cast using a permanent mould. At different ageing temperatures and time, the cast alloys were heat-treated for the improvement of tribological properties. The alloys were solutionized for 12 h at 525 °C and aged at different ageing temperatures and time. The wear processes parameter used for the present investigation were ageing temperature, ageing time, and applied load. Pin-on-Disc tribometer was used for performing the wear test. The tribological characteristics of the alloy cast were investigated using response surface methodology. The investigation found that the alloying of strontium refined the microstructure of Al–Si–Mg. It was noted from the findings obtained that there was a substantial change in the value of the specific wear rate and coefficient of friction as the wear process factors were varied. Moreover, the worn-out surface analysis on the heat-treated specimens was studied using a scanning electron microscope

Aluminium alloys have broad applications in aerospace and automotive industries due to its high strength to weight ratio. But it is found that aluminium and its alloys are having poor tribological properties, hence its applications are getting limited. Studies reveal that the additions of reinforcements will enhance the mechanical and tribological properties. In this work an investigation was carried out to understand the mechanical and tribological properties of Aluminium matrix composites. Varying weight percentage (1-5%) of tungsten carbide particulates were added to aluminium A356 alloy using stir casting technique. Different compositions of these aluminium matrix composites were cast. The tungsten carbide particulate distribution in the cast was observed using energy dispersive spectroscopy. Various Experiments were carried out to study the Mechanical and Tribological properties of these Aluminium matrix composites. The results of this investigation reveal that the mechanical properties like hardness, tensile strength and tribological properties like wear resistance have improved up to 4 weight percentage of tungsten carbide. It was also found that varying weight percentage of tungsten carbide has no influence on the coefficient of friction.

Every vehicle manufactured has a chassis design that corresponds to its body shape, size and material used, to its performance. Aluminium alloys are most commonly used due to its high strength to weight ratio. Recent studies reveal that addition of reinforcements enhance the mechanical and tribological properties of aluminium and its alloys. So in this study, keeping aluminium (A 356) alloy as the matrix, WC particulates were added at 4 wt.% to the matrix using stir casting technique. The composition and microstructure of the cast specimens were studied by using EDS and SEM. The Vickers hardness test was carried out on both as-cast and heat treated specimens. The inference was that the composite had no effect on the heat treatment. A sample design of a roll cage chassis of an off-road vehicle was designed in Solidworks. Computer Aided Engineering (CAE) analysis was carried out on both composite and A 356 alloy chassis. The analysis showed that the composite was a better choice of material selection than the conventional aluminium alloy for its improved impact resistance and high strength to weight ratio and design safety.

Tremendous researches are progressing on Aluminum Matrix composites to get along with extensive use in applications such as automobile, aerospace, marine etc. The present technology demands affordable reinforcement of industrial wastes to produce composite materials. Recent studies have shown that flyash is one of the industrial wastes for reinforcement along with Aluminum alloys which enhances the mechanical properties. The use of flyash in Aluminum Alloys reduces the density and improves the strength of composites. In the current study, the results obtained from the reinforcement of flyash in A356 alloy for various volume percentage are investigated and enhancement in the mechanical properties of automobile application (Piston) is analysed. Variation of structural properties such as deformation and strain variations are obtained. It is observed from the analysis that total deformation, directional deformation and equivalent elastic strain decreases with the addition of flyash to alloy. It is also seen that as the volume percentage of flyash increases, deformation decreases and the least deformation is observed for A356 Al C12(S)

A study was conducted to determine the effect of tin content on microstructure, hardness, optimum aging temperature and aging time of spinodal bronze alloys cast in metal mold. Copper, nickel and tin with appropriate compositions were melted in an electric furnace under argon atmosphere and were cast into metal molds. The cast specimens were solutionized at 825 °C for 10 h and were aged at 250, 300, 350, 400 and 450 °C for 1–5 h. The solutionized and aged specimens were subjected for microstructural evaluation and hardness testing. It was observed that the grain boundary precipitates form upon over-aging. The peak hardness increases with increase in tin content from 4 to 12 wt% in solutionized and aged condition. The peak aging time was found to remain a constant with increase in Sn content. The optimum aging temperature and aging time were also determined for spinodal bronze alloys cast in metal mold.

This research assessed the effect of Ti addition on the microstructure, hardness and tensile strength of as-cast Cu-6Sn alloy which is generally used to manufacture bearings, propellers and impellers. The alloying element was added in concentration of 1 wt% and the samples were cast using permanent die casting. Optical microscope and Energy dispersion spectroscopy (EDS) were used to determine the distribution of the second phase in the alloy. Vickers -hardness tester and Universal testing machine (UTM) were used in this investigation. The results indicate some influence of minor amount of Ti, the mechanical properties (Hardness, UTS, YS and %EL) of as-cast Cu-6Sn alloys were observed to improve with the addition of Ti. The improvement of mechanical properties of Cu-6Sn alloy can be attributed towards the formation of an intermediate phase due to addition of Ti. The research in these works are found to be in accordance with previous literatures.

An investigation was conducted to find the optimum aging temperature and aging time for Cu-Sn-Ni spinodal bronze alloys with varying nickel wt% cast in metal mould. The specimens were subjected to solutionisation and were aged at 250°C, 300°C, 350°C, 400°C and 450°C to induce spinodal decomposition. The microstructural observation reveals that the dendritic structure of the as-cast alloy was completely eliminated after solutionisation and grain boundary precipitates were formed with increase in aging time. The peak hardness and the peak aging time increases with increase in nickel content. This implies that nickel contributes to spinodal decomposition process.

A study was conducted to manufacture bronze metal matrix composite of varying SiC particle size (30 μm, 35 μm, 40 μm) and to determine its effect on the mechanical properties. The composites of varying SiC particle size was fabricated by liquid metallurgy route and was poured into a permanent mold to obtain cast rods. It was perceived from the study that, 40 μm SiC particle was observed to be unevenly distributed and was noted to be in an agglomerated state in the bronze matrix. The mechanical properties in the present investigation was found to enhance from the unreinforced base alloy to the alloy reinforced with 35 μm reinforced particle and then decreased at 40 μm. The decrease in the mechanical properties is due to the agglomerated condition of the ceramic particle in the matrix. The modulus of elasticity was found to increase as the SiC particles size was increased.

The increasing dependence of internal combustion engine in multitudes of application has mandated a detailed study on most of its subsystems. This paper focuses on predictive maintenance using machine learning based models. The transmission system of any power pace is often challenged due to sudden variation in applied load. Any fault in the transmission system could lead to the catastrophic failures hence need for this work. This paper deals with the identification of various fault conditions that happen in a transmission system using vibration signals acquired by an accelerometer. The acquired signals are processed to extract the statistical and spectral features. These features are used to build a machine learning model using decision tree or Random forest algorithm. The best combination of features and algorithm is evaluated and the results are presented.

The bronze alloys are expected to be used in bearings, bushings, propellers and wear plates in order to improve the performance of service. In order to have high service life, a research was conducted to analyse the titanium effect on the mechanical and wear properties of the bronze alloy. Alloys used in the present investigation were melted in an electric furnace under an inert atmosphere and were cast into a permanent mould. It was found that the hardness values of the alloys were observed to increase with an increase in titanium content and the wear rate values were found to decrease with an increase in the hardness and Titanium content. The coefficient of friction values for all the alloys was found to be independent of the hardness. Characterisation of the alloys was conducted to study the composition and wear mechanism of the developed alloys.

A detailed study was performed to find the optimum aging temperature and time for Cu-9Ni-6Sn spinodal alloy cast using permanent mould. The mechanical and wear properties of the alloy were determined and their variations with the aging temperature and time was researched for solutionised and aged condition. The as-cast dendritic structure was completely removed from the alloy after the heat treatment process. The top hardness was found to increase and then decreased with the aging temperatures and time. The optimum aging time and temperature for the Cu-9Ni-6Sn spinodal alloy were also determined. The tensile properties were found to be high when compared with that of the Cu-6Sn. The wear rate values exhibit a decrease with an increase in the hardness of the spinodal alloy. Characterisation of the spinodal alloy was conducted to discuss the wear mechanism and the fracture mode of the spinodal alloy.

Cu-Ni-Sn alloys with varying nickel wt% were melted in an electric furnace under argon atmosphere and were cast into metal mould. The specimens were solutionised at 825°C for 10 hrs and were aged at 250, 300, 350, 400 and 450°C for 1 to 5 hrs. The peak hardness was determined for different ageing temperatures and wear rate, coefficient of friction, ultimate tensile strength, yield strength and percentage elongation were determined with respect to the peak hardness. Peak hardness was found to be increasing with increase in nickel addition, wear rate decreased with increase in peak hardness, the coefficient of friction was found to be independent of hardness, ultimate tensile strength and yield strength was found to be increasing with increase in nickel content and percentage elongation decreased with increase in nickel content.