Stir Casting Method Research Articles

Experiments to find the corrosion and wear resistances and hardness of Al7075 metal matrix and NbC/Ti nanoparticles reinforcements composite

Composite material is the area of interest in the world today, for the manufacturing of the latest industrial and domestic equipments and the air, sea and road vehicles. They all require materials with special properties like high strength, corrosion and wear resistances, high hardness, light weight, easy for maintenance, cost effective etc. The airspace vehicles exemplify the composite materials with aluminium and its alloys as the base metal for their components, since they are lighter in weight, which is the prime requirement. To obtain the properties needed for each component, the suitable reinforcements are added to the matrix, which may also enhance the required properties. In this paper, Al7075 is used as the matrix and niobium carbide and titanium nanoparticles are selected for the reinforcements. Al7075 is very strong and light material, Niobium carbide has a melting point of 3490 °C, and titanium is highly corrosion resistant. These properties of the reinforcements gave the objective of finding a material for the marine engine components. The various compositions were Niobium carbide nanoparticles 5%, 10% and 15% and titanium nanoparticles 2%, 4% and 6% respectively with Al7075. Then the three samples of this composite were manufactured using the stir casting method and the corrosion, wear and hardness tests were conducted on these samples. The best results were obtained in 10% NiC and 4% Ti composition.

Optimization of process parameters on wire cut electrical discharge machining and surface integrity studies of AA6070/MgO composites

There are a variety of uses for metal matrix composites (MMC), including the aerospace and automotive industries. Because of their benefits including light weight and inexpensive cost, they are popular. Wire cut electric discharge machining (WEDM) stands out as a great option for creating complex or complicated shapes out of composite materials, especially when compared to other common non-traditional machining processes. An AA6070 metal matrix composite containing 5% and 10% MgO weight fraction (wt) was made using the stir casting method in this work. Various process factors, such as wire tension (WT), dielectric pressure (Pd), gap voltage (Vg) and peak current (IP) are taken into account when the AMMC specimen is machined utilising WEDM. Slot machining rate (MR) and surface roughness (Ra) can be measured and assessed using L18 mixed Orthogonal Array (OA) investigations. Experiments are examined using TOPSIS and ANOVA methodologies for order preference based on similarity to the ideal results (ANOVA). Analysis has shown that the best mixture of processing factors for improved MR and Ra: wt = 5%, vg = 50 V, WT = 13 g, Ip = 9 A, and Pd = 15 bar. Machining Rate and Ra have ideal process parameters of 1.5 mm/min and 3.648 m. ANOVA shows that MR and Ra are significantly influenced by peak current.

Tribological characteristics of aluminium alloy composites manufactured by liquid state casting process – A review

The global requirement for good quality and superior performing composites has led to research in hybrid metal matrix composite materials. In metal matrix composites, Al alloy composite has been chosen widely because of its high strength-to-weight ratio and superior wear resistance. Reinforcements like particulate Al2O3, SiC, fly-ash and graphite, etc. can easily be included in the melt using a liquid state casting process. In order to fulfil the essential need for elaborating their application, conventional stir casting method is employed which is economical for fabricating composite material when compared to other solid-state and liquid-state processes. This paper mainly focuses on the tribological properties and problems incorporated at the time of stir casting process of aluminium alloy composites containing one or more reinforcements. It provides inputs on the reinforcement incorporated, the matrix composition and the interface overlap and distribution each of which is critical in determining the performance of the composite. Processing AMMCs is straight forward using stir casting process, which is the most inexpensive and robust process that can be used on a wide scale, while other methods are confined to laboratories alone.

Correlation of Structural and Mechanical Properties for Ultrasonically Stir Casted Al6061 Reinforced SiC-AlN Hybrid Metal Matrix Composites

In our current investigation, Al6061-SiC-AlN composites were manufactured using the ultrasonic stir casting method. As reinforcement, silicon carbide (SiC) and aluminium nitride (AlN) [both 3 percent and 6 percent by wt.] were used to provide mechanical properties including tensile, compressive, and hardness. Al6061-SiC-AlN hybrid composite samples’ tensile strength, compressive strength, and hardness were measured. Al6061-SiC-AlN hybrid composites’ tensile, compressive, and hardness properties are calculated and compared to those of the matrix i.e. Al 6061 alloy. The tensile strength, compressive strength, and hardness all rose from 328 to 385 MPa, 145 to 178 MPa, and 302 to 724 VHN, respectively, with the addition of SiC and AlN nano-reinforcements. The suggested composite is compared to unreinforced Al6061 in terms of density and mechanical qualities such ultimate tensile strength, yield strength, impact strength, hardness, and wear characteristics. The results of the experimental examination showed that the produced hybrid composite, which contains 20% of the total reinforcing material, has no appreciable increase in impact strength but displays high hardness, high yield strength, and low wear rate.

Processing and evaluation of nano SiC reinforced aluminium composite synthesized through ultrasonically assisted stir casting process

Aluminium composites were synthesized through an ultrasonically assisted stir casting method by reinforcing 0.5 wt%SiC, 1.0 wt%SiC, 1.5 wt%SiC and 2.0 wt%SiC nanoparticles. Ultrasonication was carried out to the composite melt to refine the grain size and to achieve uniform nano-SiC dispersion in the aluminium matrix. Scanning electron microscopy (SEM) reveals the uniform dispersion of nano-SiC particles in the 0.5 wt%, 1.0 wt% and 1.5 wt% SiC reinforced compose. However, the X-Ray Diffraction (XRD) peaks confirm the Al2Cu intermetallic phases in the Al- 2.0 wt% SiC composite. The mechanical properties of the synthesized composites were significantly enhanced with the incorporation of SiC reinforcements and the maximum hardness and ultimate tensile strength (U.T.S) of 163 BHN and 431 MPa was attained for 1.5 wt% SiC reinforced composite. Nevertheless, the generated brittle agglomeration at 2.0 wt% SiC reinforcements decreases the mechanical properties of the composite due to the variation of thermal expansion coefficients between the matrix and the agglomerations. The yield strength of the fabricated Al– SiC composites was analyzed through different strengthening mechanisms. Results concluded that the yield strength contribution due to thermal mismatch is more influenced followed by the Orowan strengthening and grain refinement strengthening mechanism. In addition to this, the contribution of the strengthening mechanisms was found to be increased with the addition of SiC nanoparticles. Fractography investigation for the fractured tensile specimens reveals the ductile fracture for unreinforced aluminium and brittle fracture for the SiC-reinforced composites due to the presence of cleavage texture of the fractured surfaces of Al–SiC nanocomposites.

Microstructure and mechanical properties of AZ91D/Si3N4 composites using squeeze casting method

The material utilized in the aerospace and automotive industries must be capable of withstanding significant loads while maintaining a minimal structural weight. In pursuit of novel lightweight materials for industrial applications, magnesium is quickly displacing aluminum-based alloys. In this study, a magnesium (AZ91D) matrix composite reinforced with nano ceramic silicon nitride (Si3N4) of varying weight proportion (2 wt%,4 wt% and 6 wt%) was synthesized using vacuum stir casting method. The microstructural study of uniform distribution of nano Si3N4 particles are revealed by an optical microscope. Micro hardness (26.8%) and tensile strength (32.12%) increased with increasing weight percentages of Si3N4 particles in a magnesium alloy matrix, whereas percentage of elongation decreased (6.52%). With an increase in weight% of Si3N4 particles in the magnesium matrix, the porosity of composites decreased (1.02%) and density of composites increased to minimum (0.06%). The corrosion characteristics were examined using B117 salt spray test. The test illustrated that an increase in percentage of reinforcement accelerates corrosion resistance (17.52%) due to induced segregation, dislocation, and micro crevice formation. Based on the results, it can be concluded that the manufactured composite can be employed in a variety of industrial applications where lighter structural materials are required.

Identifying regularities of high temperature on constant and variable fatigue life of AA7075-Al2O3 nanocomposite fabricated by stir casting method

This study aims to determine the effect of high temperature on the fatigue life of AA7075-Al2O3 nanocomposites (6 wt % Al2O3) fabricated by stir casting. The research problem is to determine the durability, fatigue resistance, and mechanical properties of the nanocomposite under constant and variable loading conditions at elevated temperatures, as well as to identify changes in its behavior due to exposure to high temperatures. The results show that higher temperatures have a big effect on the nanocomposite's fatigue performance under both loading conditions. When the material was tested at a high temperature (150 °C) with an extra 6 wt % Al2O3, the ultimate tensile strength and yield stress both went up by 16 % and 15.7 %, respectively. Its fatigue life was also successfully tested under both variable and constant amplitude load conditions. The interpretation of the results suggests that the changes in the microstructure of the nanocomposite material at elevated temperatures lead to an increase in dislocation density and grain size, resulting in an improvement in its mechanical properties. The findings can be utilized to optimize the nanocomposite fabrication process and enhance its fatigue resistance at high temperatures. In addition, the results can be used to enhance the design of aerospace components and high-temperature engines that require materials with excellent fatigue resistance at elevated temperatures. In summary, the investigation of the effect of high temperature on the constant and variable fatigue lives of AA7075-Al2O3 nanocomposite provides valuable insight into the material's mechanical properties. The findings contribute to the development of materials that can withstand high-temperature conditions, which has implications for a variety of industries.

Optimization on Stir Casting Process Parameters of Al7050/Nano-B4C Metal Matrix Composites

Aluminum matrix composites are widely employed in aerospace, military, automobile, and transport applications. The high-strength with low-weight materials are required to fulfill the requirement of high-performance applications. The low-weight materials are reinforced with hard reinforcements to obtain high-strength-to-weight properties for using high-performance applications. The process parameters of fabrication technique define the mechanical and tribological properties. Many types of optimization tools are used for optimizing the process parameters of fabrication method. In this research, the aluminum alloy 7050 and boron carbide are selected as matrix material and reinforcement material. The fabrication of Al7050/B4C composites is produced by the stir casting method. The optimization on stir casting process parameters is done by using the Taguchi approach. The L9 orthogonal array is chosen for this investigation. The chosen input stir casting process parameters are wt% B4C, stirring time (10, 15, and 20 min), stirring speed (300, 350, and 400 rpm), and melting temperature (700, 750, and 800°C). The microhardness is selected as a valuable response parameter for optimizing the stir casting process parameters. The influencing stir casting process parameter sequence is determined by using mean table. The influencing parameters of stir casting on microhardness are stirring speed, stirring time, wt% B4C, and melting temperature. The 9 wt% of boron carbide addition increases the microhardness, and it is higher than the other wt%. The optimum combination of input process parameter combination is 9 wt% boron carbide, 750°C melting temperature, 350 rpm stirring speed, and 15 min stirring time (A3B2C2D2). The percentage of microhardness value improvement is 20.3%.

Influence of MgO & SiC on Mechanical and Wear Characteristics of AA6061 Hybrid Matrix Composites Synthesized by Stir Casting

Aluminium alloy related to Metal Matrix Composites (AMMC’s) have been achieve enormous comprehensive acknowledgment for aerospace and structural applications, due to its excellent corrosion resistant, good wear resistant, high strength and light weight. In this paper, the experimental study deals with investigation influence of reinforcement (Magnesium oxide and Silicon Carbide) particles on various mechanical properties of aluminium alloy (Al 6061). AMMC was fabricated by stir casting method. The exsitu method was used to fabricate because of its less complexity. The MMC specimens with different weight percentage of reinforcement particles such as 3%, 6% and 9% were prepared. After the fabrication, the ingots were machined for preparation of test samples. The tensile, compression, Impact and hardness test were taken to study the mechanical properties and effect of varying weight percentage of reinforcements. As the outcome, the tensile and compression strength were progressively increase with addition of magnesium oxide and silicon carbide.

Mechanical and microstructural behavior of industrial spent catalyst waste and boron carbide reinforced aluminum matrix composites

The concept of reuse and recycling has undergone sustained development in industries to prevent the exhaustion of naturally available resources. The current study is about reusing spent catalyst waste from petroleum refining industries as reinforcement in aluminum composite materials. This work utilized the stir casting method to create nano B4C/waste spent catalyst/Al matrix composites by varying the B4C from 0.5 to 2.0 wt% and maintaining the constant 10 wt% of spent catalyst waste, respectively. Furthermore, the impact of nano B4C and spent catalyst waste on the mechanical and microstructure behavior of aluminum matrix hybrid composites were studied. The compressive strength, hardness, and tensile strength of the aluminum composites obtained with different percentages of nano B4C and spent catalyst waste were enhanced significantly. The increase in tensile strength mainly due to the effect of the Orowan strengthening mechanism and thermal stresses caused by the difference in the CTE of aluminum matrix and reinforcement. The effective mechanical behavior was obtained with 1.5 wt% B4C and 10 wt% spent catalyst waste with massive improvements in hardness (65.62%), compressive (31.81%), and tensile strength (48.23%), respectively, compared to base pure aluminum.

Influence of hybrid reinforcements on the mechanical properties and morphology of AZ91 magnesium alloy composites synthesized by ultrasonic-assisted stir casting

In the present study, AZ91 magnesium alloys reinforced with a fixed weight fraction of aluminium oxide (Al2O3: 1.5 wt%) and titanium di-boride (TiB2: 1, 3, and 5 wt%) particle hybrid metal matrix composites were developed using the stir casting method assisted with ultrasonic agitations. The microstructural analysis reveals that the structure of monolithic alloy is made up of α-Mg grains with evenly distributed β-Mg17Al12 intermetallic secondary phases near the grain boundaries. Incorporating hybrid reinforcements into the matrix alloy decreases the average grain size and also leads to the breakdown of the β-Mg17Al12 phase from a rounded shape to sharp needle-like profiles. The micro-hardness, ultimate tensile strength, and impact strength outcomes revealed a direct correlation with varying TiB2 particulate contents, the peak values of which have been achieved with the addition of 3 wt% of TiB2 particulates with AZ91 + 1.5 wt% Al2O3 hybrid composite.

Characterization of wear and fatigue behavior of aluminum piston alloy using alumina nanoparticles

Abstract Due to their excellent thermal conductivity, lightweight, and ease of processing, aluminum alloys are the material of choice for piston manufacture in internal combustion engines. Nanoparticles (NPs) of alumina (Al2O3) with a size of 25 nm were incorporated into an aluminum piston alloy to examine the effect of the NP addition on wear resistance and fatigue behavior. The stir casting method has been utilized to manufacture experimental samples of the composite material by altering the particle weight ratio of aluminum to the matrix alloy to 2, 4, and 6 wt%. The surface morphology of the samples has been examined using an electronic scanning microscope. The results of the wear and fatigue tests indicate that the addition of Al2O3 to the composite enhanced its fatigue resistance and wear strength, with the exception of 6 wt% weight ratio. The best improvement in wear resistance and fatigue strength occurs at 4 wt% Al2O3 particles, which are 12.13 and 67.5%, respectively, more significant than the pure metal and other composites. The mechanical properties of the alloy samples have been enhanced by adding Al2O3 NPs of 25 nm size into the piston’s aluminum matrix alloy. Stir casting was employed to produce the needed composites by incorporating Al2O3 NPs at varied weight percentage ratios of 0, 2, 4, and 6 wt% into the master alloy. Before the composite alloy reached 6 wt%, including Al2O3 NPs, the alloy’s hardness and tensile strength improved, according to the experiment results.

Optimization of the Stirring Parameters of AZ91Mg-Based Stir Casted Hybrid Composites Using Taguchi and ANN

In the current research, the fabricated Mg hybrid composites amalgamate with the vacuum-based squeezed stir casting process having TiC and Al2O3 reinforcement’s in which AZ91Mg-alloy is the base material. The study includes the processing parameters of the vacuum-based squeezed stir casting method (such as stirring time, stirrer depth, and stirring speed) that have been varied and then investigates their influential effect by using the L16 orthogonal Taguchi approach. By considering these parameters, the tribo-mechanical properties are also optimized like porosity, ultimate strength, and rate of wear loss of Mg-hybrid composites. The result reveals a significant association between processing parameters and optimized tribo-mechanical properties. The results signify that the processing parameters are best optimized at processing parameters of 500 rpm of stirring speed, 5 min of stirring time, and 50 mm of stirrer depth and the optimized tribo-mechanical properties are 0.4% porosity, 245 MPa of ultimate strength, and 0.0011 mm3 per min is the loss of wear rate. However, the ANOVA results contribute that the stirrer depth has the most significant processing parameter compared to other optimized parameters. This research also includes an artificially designed networking model which validates the designated set of empirical data. Thus due to their suitability for abrasion wear AZ91-hybrid composite gives a new divergence towards the designing parts of minuscule airplanes used in surveillance applications such as ailerons and wing flaps.

Investigation of the Mechanical and Machinability Characteristics of Al6061 Composites Reinforced with B4C Particles

Abstract: Metal matrix composites especially Aluminium metal matrix has emerged as structural materials satisfying all requirements basically light weight, high strength values and high toughness values. The improved mechanical properties combined with the savings in weight have paved way for engineering applications in automotive, aerospace applications. This is due to the exhibiting superior properties compared to the base matrix. It has also replaced conventional materials when specific properties are demanded for the required applications. In the present work, successful attempts were made to reinforce Boron carbide (B4C – 4 to 10% in steps of 2%) additions using stir casting method with copper (CU) chill material embedded in mould. Mechanical properties such as UTS, hardness have been studied. Machinability studies has been carried out using turning tests. The influence of cutting parameters namely feed, speed and depth of cut has been studied with respect to the power consumption. Cutting forces were measured by varying spindle speed, feed and depth of cut. Results indicate the improvement in mechanical properties with addition of B4C and the castings made in Cu chill exhibits higher values of UTS and hardness. From the machinability studies it is observed that the power required to machine composite increases with increase in the B4C additions.

Effects of Electrode Heating in Electro chemical Micro Machining

Abstract: Composite materials are widely used in various applications and extensive research has been performed to better understanding of mechanical behavior of such materials for taking maximum advantage of their properties. Composite materials have played an important role in particular, aluminium composite offer many benefits i.e., the key amoung them are corrosion resistance, design flexibility, durability, light weight, and higher strength. Some of the applications of composite such as automotive, aerospace, defence etc.in this project work, aluminium 6061 used as matrix material and cerium oxide acts as a reinforcement.AI composites are fabricated by the stir casting method. In addition, machinability study of AI composites through electrochemical micromachining process.in this machining process, input voltage, duty cycle, electrolyte concentration and % of different reinforcement samples are considered as input parameters whereas, material removal rate, radial over cut are considered as response parameters. Effects of these parameters are studied and reported in future.

Study of the corrosion, electrical, and mechanical properties of aluminium metal composite reinforced with coconut rice and eggshell for wind turbine blade development

The gradual global shift from fossil fuels to renewable energy sources such as wind energy for power generation has stirred up a perpetual exigency for sustainable materials for manufacturing wind turbine blades. AMMCs are categories of materials that, over time, have proven reliable as they have been successful in meeting engineering needs in applications requiring high stiffness, moderate strength, and lightweight. The Al8112 alloy was used as the base metal in this study, reinforced with coconut rice and eggshell, to study the corrosion, electrical, and mechanical properties as a viable material for the development of the wind turbine blade. The stir-casting method was used in the preparation. Microstructures, Vickers hardness, tensile strength, electrical conductivity, and corrosion analysis (via the weight loss method) of the prepared composites were analysed. The 3 samples A, B, and C were analysed under 3 media for the corrosion study, such as rainwater, coolant (soluble oil plus water), and nano-lubricants. The results showed that introducing the reinforcements in the matrix of coconut rice and eggshell caused a rise in the hardness and tensile strength. SEM and EDX microstructural analysis revealed a uniform distribution of reinforcement particles in the matrix with the elemental reactions. The corrosion resistance of sample C of the composition (92% aluminium alloy, 5% coconut rice, and 3% eggshell) proved to be higher than that of sample B of the composition (95% aluminium alloy, 2.5% coconut rice, and 2.5% eggshell, and that of the aluminium alloy sample A, with sample C having a corrosion rate of 0.020 mg, sample B having a corrosion rate of 0.021 mg, and sample A having a corrosion rate of 0.022 mg. The composition of the AMMC that exhibits these properties is 92% aluminium, 5% coconut rice, and 3% eggshell. This newly developed material is recommended for applications involving the wind blade.

Al2014-Alumina Aerospace Composites: Particle Size Impacts on Microstructure, Mechanical, Fractography, and Wear Characteristics.

An Al2014-alumina (Al2O3) composite's characteristics are significantly influenced by the reinforcement particle size variation. Therefore, this study examines the microstructure, mechanical, fractography, and wear performance of an Al2014-Al2O3p composite made using a unique two-stage stir casting method and various alumina weight fractions (9, 12, and 15 wt %). Three categories of alumina particle size are used, i.e., fine particle size (FPS, 8 μm), intermediate particle size (IPS, 53 μm), and coarse particle size (CPS, 88 μm). The shapes of the composites were characterized using scanning electron microscopy. According to scanning electron microscopic analyses of the microstructure, the FPS dispersion was more uniform than IPS and CPS, whereas CPS causes agglomeration. Additionally, the studies show that the FPS composite outperformed CPS and IPS composites in terms of mechanical characteristics and wear performance. The fractography study shows conical and equiaxed dimple failure in the Al2014 matrix and the circular cavities.

Fabrication of Aluminium Hybrid Metal Matrix Composite Reinforced with Silicon Carbide and Graphite by Stir Casting Method

The AA2014/SiC/Gr hybrid metal matrix composites are developed with addition of 0.5% to 1.5% SiC particles (weight fraction) in 0.5% weight fraction interval and the graphite (Gr) is 1% weight fraction constant for all composites were prepared by stir casting method. The effects of SiC and Gr on the microstructural and mechanical properties of the base cast and hybrid composites were studied by SEM, hardness, and impact tests. The results indicate that mechanical properties of the aluminium hybrid metal matrix composites (AHMMCs) change according to their increment of SiC and Gr particle. The hardness and impact strength of base cast and hybrid composites increased during the addition of SiC and Gr particle. The hardness and impact strength of base cast and hybrid composites increased during the addition of SiC and Gr particle. The maximum hardness is observed in the fourth sample with 1% Gr and 1.5% SiC with 7% increment which is 102.4 VHN. The high impact strength was observed for base alloy of 24% than hybrid composite. The composite of 1% SiC and 1% Gr is given less wear loss and coefficient of friction. The Corrosion resistance is better in the composite of 0.5% SiC and 1% Gr and the optical micrographs shows that the composite with 0.5% SiC and 1% Gr shows good texture.

Hardness and Wear Behavior of Heat Treated Aluminium Silicon Alloy SiC Particle Reinforced Composite

The A356 Aluminium Silicon alloy is reinforced with Silica Carbide particles (SiCp) to form metal matrix composite by stir casting method to study the hardness and wear properties. The composites are prepared for weight fraction of 2, 4 and 6% of SiC with the base alloy and their characteristics are observed at post T6 full heat treated condition. The optical microscopic metallography observation shows the rosettes of uniform spheroidal grains of strain free eutectic silicon phase in proeutectic Aluminium matrix after heat treatment. The hardness and wear properties of the A356-SiC composites have increased with the increase in weight percentage of reinforcement particle in the base alloy. Maximum hardness and wear resistance is observed for 6% SiC which is the maximum percentage of inclusion of secondary element considered under this study. A comprehensive discussion is made on the strengthening of the A356 alloy on addition of hard SiC particles that has improved the hardness and wear characteristics of composites in heat treated conditions.

ASSESSMENT OF TRIBOLOGICAL PROPERTIES OF STIR CAST Al6063 ALLOY REINFORCED WITH OKABA COAL ASH

Composite are multi-phase materials made up of matrix and reinforcement. This paper assesses the tribological property of Al6063 alloy (AMCs) reinforced with Okaba coal ash (OCA) using the stir casting method. By using a constant speed of 1000 rpm and two different loads (250 g and 750 g) on Taber wear apparatus, the tribological properties of the produced composite are contrasted with those of an unreinforced Al6063 alloy. The results show a reduction in wear index and the highest abrasion resistance at 4 wt.% coal ash at 500 g and 1000 rpm, as well as at 0, 2, and 6 wt.% with 8.688, 5.878, and 5.813 at 500g and 8.688, 5.878, 4.125, and 5.813 at 750g, respectively. Therefore, for all composite products compared to metal, there is an increase in abrasion resistance with a decrease in wear index, but this decreases when the load is increased to 750g, showing that the higher the load, the higher the wear index, which results in a reduction in abrasion resistance. Load is taken into greater consideration when using the AMCs manufactured in engineering applications. Additionally, SEM images revealed uniform distribution of the OCA reinforcement in the matrix alloy; thereby, improving its wear resistance.