Ultrasonic Assisted Stir Casting Research Articles

Fabrication and wear analysis of Al 8009-TiB2 composites produced by ultrasonic assisted stir casting

Fabrication and wear analysis of Al 8009-TiB2 composites produced by ultrasonic assisted stir casting

Recent Advancements in Fabrication of Metal Matrix Composites: A Systematic Review.

Metal matrix composites (MMCs) are essential materials in various industries due to superior properties, such as high strength-to-weight ratios, better corrosion resistance, improved wear resistance and adaptability, developed by continuous improvements in their fabrication methods. This helps to meet the growing demand for high-performance and sustainable products. The industries that stand to gain the most are automotive and aerospace, where MMCs are used for car parts, airplane frames, and jet engines that need to be strong and lightweight. Furthermore, MMCs are being extensively used in the biomedical industry for implants and medical equipment because of their suitable mechanical integrity and corrosion resistance. Applications in heavy construction, defense, and even space exploration are noteworthy. The advancements in fabrication of MMCs have revolutionized the composite industry with their improved mechanical, tribological, and metallurgical properties. This review article offers an introduction and thorough examination of the most recent advancements (mostly within the last five years) in fabrication methods of MMCs. The novelty and modernization in the traditional processes and advanced processes are covered, along with discussing the process parameters' effects on the microstructure and properties of the composites. The review focuses on features and prospective applications of MMCs that have been greatly improved and extended due to such advancements. The most recent methods for developing MMCs, including friction stir processing (FSP), ultrasonic-assisted stir casting, and additive manufacturing, are discussed. Artificial intelligence and machine learning interventions for composite manufacturing are also included in this review. This article aims to assist researchers and scholars and encourage them to conduct future research and pursue innovations to establish the field further.

Analyzing the synergistic effects of hard ceramic TiB2 and rare earth oxide La2O3 on mechanical behaviour, wear resistance, and residual stress of AA6061-T6 hybrid composite fabricated via ultrasonic-assisted stir casting

This investigation involves the fabrication of an aluminium metal matrix composite using AA6061-T6 alloy as the matrix, incorporating 2 wt% of hard ceramic (TiB2, 14 μm particle size) and 0.5 wt% of rare earth oxide (La2O3, 40–50 nm particle size) reinforcement powders through ultrasonic assisted stir casting. The study examines the microstructure, residual stress, and mechanical properties alongside performing pin-on-disk wear tests. Taguchi's optimization and ANOVA are used to optimize the wear rate of the composite using three control parameters: Load, Sliding Distance, and Sliding Speed. Results from optical micrography and field emission scanning electron microscopy (FESEM) with energy-dispersive spectrometer (EDS) analysis confirm the uniform distribution of TiB2 and La2O3 particles within the AA6061-T6 volume when ultrasonic stirring is employed. The composite's microhardness is found to increase by 25.15 %, and its tensile strength by 31.32 % compared to the base alloy due to a higher dislocation density. ANOVA highlights Load as the primary influencer, contributing 69.54 %, followed by Sliding Distance (17.45 %) and Sliding Speed (12.56 %). The optimal parameters for minimizing wear rate are found to be Load (20 N), Sliding Distance (1500 m), and Sliding Speed (2.5 m/s). Scanning Electron Microscope (SEM) images of worn surfaces reveal various mechanisms such as abrasion, delamination, and adhesion, with abrasion being the dominant mechanism. Residual stress increases with the addition of TiB2 and La2O3 particles in the matrix, showing transitions from tensile to compressive stress from the inner to the outer surface of the composite casting.

Effect of sliding speed and sliding distance on wear behavior of AZ31-B4C composite

Emphasis of current research is to investigate the dry sliding behavior of AZ31 magnesium alloy and AZ31–1.5B4C magnesium metal matrix composites (MMCs) at varying sliding speeds and sliding distances. Magnesium alloy and composite are fabricated through ultrasonic assisted stir casting method. Optical microscope (OM), scanning electron microscopy (SEM), and energy dispersive x-ray analysis (EDAX) are used to characterize developed materials. Microhardness of all materials is measured using a Vickers microhardness tester. Wear-friction behavior is investigated in dry sliding mode using pin-on-disc tribometer at room temperature. Magnesium alloy and composite are tested over a range of sliding speeds (0.25–1.25 m s−1) and distances at a moderate normal load (20N). Wear morphology is finally investigated for composites and alloy under SEM and EDAX. SEM micrographs of as-cast AZ31-1.5B4C composite reveals uniform distribution of B4C particles with noticeable refinement in grain structure. EDAX spectra of AZ31-1.5B4C composite depict the presence of boron and carbon along with existing elements of AZ31 alloy. Microhardness has enhanced around 30% for Mg-MMC by incorporating 1.5 wt% B4C in AZ31 alloy. Furthermore, the use of B4C as reinforcement increases the density of the composite. Wear rate is reduced by around 20% and COF is reduced by around 25% for AZ31-1.5B4C composite compared to AZ31 alloy for all experimental conditions. Abrasion, oxidation, adhesion and delamination wear mechanisms are observed as dominant mechanism for varying sliding speeds and distances.

A study on the effects of hybrid (SIC- PSSA) nano sized reinforcement on mechanical and tribological behaviour of Al alloy-based metal matrix composite produced by ultrasonic assisted stir casting

This study focuses on the effects of hybrid reinforcement consisting of nanosized particles of Palm Sprout Shell Ash (PSSA) and silicon carbide (SiC) on the mechanical and tribological properties of the Al-Cu-Mg alloy. Hybrid reinforced composites with different weight percentages of SiC and PSSA (0:0, 0:4, 1:3, 2:2, and 4:0 wt%) were prepared using the ultrasonic-assisted bottom-poured stir casting technique. Scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS) were used to characterize the hybrid composite made of Al-Cu-Mg alloy. The optical and SEM microstructural analyses demonstrated an even distribution of SiC and PSSA nano size reinforcements within the matrix. The EDS analysis revealed SiC and PSSA reinforcement particles in the composite. The mechanical properties (tensile, flexural, and impact strength) and wear properties (wear rate and coefficient of friction) of the composites and alloys were evaluated according to the ASTM standards. The hybrid reinforced composites outperformed the base alloy. Among all composites, the 2:2 wt% SIC and PSSA hybrid reinforced composites exhibited a significant enhancement in both tensile and flexural strength, with a 29.15% and 27.64% increase in strength, respectively. However, the inclusion of these reinforcements led to a reduction in the ductility and impact strength of the Al-Cu-Mg alloy composite. The 0:4 wt% SiC- and PSSA-reinforced composites experienced the largest reductions in ductility and impact strength, with decreases of 47.67% and 3.56%, respectively. For the 2:2 wt% SiC and PSSA composites, these reductions were 23.64% and 3.16%, respectively. The SEM analysis of the fractured surfaces of the composites tested for mechanical properties revealed evidence of both ductile and brittle fracture mechanisms in the tensile, flexural, and impact tests. The wear behaviour of the prepared samples was evaluated, and all composites exhibited superior performance compared with the base alloy, demonstrating adhesive and abrasive wear mechanisms and varying friction coefficients. Among all the composites, the 2:2 wt% SiC- and PSSA-reinforced composites exhibited high wear resistance and a lower coefficient of friction than the other fabricated composites.

Microscopic investigation on micro electric discharge milling of AA6063-SiC composites

Metal matrix composites (MMC) have found applications in places where the utilization of conventional materials is limited. This also includes areas of micro- and meso-applications. However, micromachining of metal matrix composites by conventional methods poses difficulties due to the heterogeneous nature of the material and the presence of hard reinforcement particles. Micro-ED milling is a versatile micromachining process used to machine hard engineering materials. It employs a simple cylindrical cross-section tool, which is rotated and fed in predefined paths to generate intricate 3D features with good dimensional accuracy and surface finish. In order to study the machining performance of micro-ED milling process on metal matrix composites, micro-ED milling of AA6063-4 wt.% SiC composite fabricated by ultrasonic-assisted stir casting was carried out. The tool feed rate and tool rotation speed are important parameters as they aid in debris evacuation and influence material removal. So, the effect of tool feed rates, tool rotation speeds and discharge energies on the surface morphology and surface roughness of the machined channels were studied. The surface roughness parameters, namely Sa and Sq, were considered for the study. The least surface roughness, Sa and Sq, was observed at 2 µm/s for all the investigated discharge energies.

Variation in wear scar penetration depths due to impact angle on the erosion wear of advanced aluminum matrix nanocomposites

In present study, developing (Al-Fe-Si) materials with high wear and erosion resistance for aerospace components, such as wing skin and fuselage sections, presents a significant challenge for researchers. This study delves into the reinforcement effects of TiC in aluminum composites, produced via ultrasonic-assisted stir casting. The focus lies on exploring the UASC technique to create composites with varied TiC weight percentages (0 %, 2 %, 4 %, and 6 % by weight) and evaluating their erosion resistance. Experiments varied erodent particle impact angle, velocity, and discharge rate, alongside impingement angles, and maintaining a constant velocity of 151 m/s for 10-minute durations, using solid particles averaging 201 µm in size. Increasing TiC content improved erosion resistance. Optical profilometry revealed a −131 µm maximum wear scar depth at a 45° impingement angle, with significantly higher erosion wear compared to other angles. These findings offer valuable insights for enhancing mechanical system design and durability. Eroded surface failure analysis utilized FE-SEM images to examine composites impacted by erodent forces.

An investigation of machinability in micro-EDM drilling of ZrB2/Fly ash/AA7075 hybrid aluminium metal matrix composite

This work investigates the importance of micro-drilling in Hybrid aluminum metal matrix composites (HAMMCs), particularly for the aerospace and automotive industries. The HAMMCs (AA7075/5% ZrB2/2% fly) ash was fabricated using the ultrasonic assisted stir casting method. Taguchi’s design of experiments is employed to optimize the material removal rate (MRR) and tool wear rate (TWR). Analysis of variance (ANOVA) is then used to determine the significance of the model. The study also utilizes a hybrid artificial neural network-genetic algorithm (ANN-GA) approach to optimize both MRR and TWR. By optimizing machining processes for HAMMCs, manufacturers can achieve high-precision micro holes. The optimal input parameters were found to be a feed rate of 10 μm sec−1, a capacitance of 1 nF, and a voltage of 85 V, achieving the minimum TWR and maximum MRR.

Tribo-informatics approach to predict wear and friction coefficient of Mg/Si3N4 composites using machine learning techniques

The demand for lightweight, high-performance materials has driven significant advancements in magnesium-based materials. However, their practical implementation faces challenges, primarily due to their low wear resistance, especially in industries like automotive, where weight reduction is vital for fuel efficiency. Furthermore, the process of fabricating and assessing wear behavior incurs time and cost constraints. In light of this, machine learning techniques have emerged as a crucial tool for predicting the mechanical properties, wear characteristics, and tribological performance of diverse materials, including magnesium and its composites. Accordingly, the present study aims to integrate experimental results with machine learning techniques. The objective is to predict the wear rate and friction coefficient of Mg/Si3N4 nanocomposites, thus optimizing material design and manufacturing for superior wear performance. Nanocomposites are fabricated through ultrasonic-assisted stir casting, and a dataset of 120 data points is collected using a pin-on-disc tribometer under dry sliding conditions. Five supervised machine learning regression models are employed to predict wear rate and coefficient of friction, with hyperparameter tuning for a fair comparison. Results are evaluated using various statistical metrics, identifying the most effective model for accurate wear behavior prediction. The study also demonstrates improved wear resistance and lower friction coefficients in nanocomposites compared to pure magnesium. This is attributed to the even distribution of Si3N4 nanoparticles and strong interfacial bonding with the matrix. The presence of a mechanically mixed layer further enhances wear resistance under high loads and speeds. Five wear modes are identified, including abrasion, oxidation, adhesion, delamination, and plastic deformation, providing valuable insights into the wear mechanisms. A comprehensive wear map facilitates a deeper understanding of wear behavior.

Abrasive wear behavior of AZ31 −B4C composites

Abrasive wear behavior of AZ31 −B4C composites having varying amount of B4C particles (0 −2 wt%) is investigated. AZ31 −B4C composites are synthesized through ultrasonic assisted stir casting method. Characterizations of as-cast composites are performed through optical microscopy and field emission scanning electron microscopy. Compositional analyses are performed using energy dispersive X-ray analysis (EDS). Microstructural analyses disclose uniform distribution of B4C ceramic particles in AZ31 matrix. Compositional analyses confirm incorporation of B4C particles in AZ31 matrix. Both microhardness testing and density measurements are performed. Microhardness value is enhanced by 54.9% compared to base alloy by incorporating 2 wt% of B4C particles. Pin-on-disk tribotester is employed to scrutinize abrasive wear and friction characteristics of developed materials at varying sliding distance (40, 50 and 60 mm track dia.) and different abrasive grits (400, 500 and 600 grit). Wear rate of AZ31 alloy is about 1.3 − 1.5 times more than AZ31 − 2.0B4C composite for all experimental conditions. Wear rate reduces with increase in abrasive grit size while the same increases with increase in sliding distance. Finally, worn surface morphology of developed materials is also analyzed through FESEM and EDAX spectra. Examination of worn surface morphology discloses that abrasion and oxidation are dominant for composite samples.

Mechanical and wear characteristics of (Al7075/SiC/Gr/Zr) hybrid metal matrix composites using ultrasonic assisted stir casting process

Mechanical and wear characteristics of (Al7075/SiC/Gr/Zr) hybrid metal matrix composites using ultrasonic assisted stir casting process

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.

Development of Al 7075 alloy with nano SiC Composites through ultrasonic assisted stir casting Techniques and Mechanical Testing of Properties

ABSTRACT Al-7075 alloy with nano-SiC composite has superior mechanical properties that can be used in automobile, aerospace and defence sector to manufacture various components and body structures. In the present study, Al-7075 alloy with nano-SiC composite with different wt% of nano-SiC particles has been fabricated by the ultrasonic-assisted stir casting method. Uniform mixing of the nanosized SiC particles in the Al-7075 alloy has been achieved from ultrasonification and as-cast and T6 heat-treated samples were prepared. The diverse mechanical properties such as tensile strength, impact strength and hardness have been examined for the as-cast samples with different wt% of nano-SiC and T6 heat-treated samples.

Optimization of process variables on Electrical Discharge Machining of novel Al7010/B4C/BN hybrid metal matrix nanocomposite

In this paper, determination of optimum EDM input variables like discharge current (DC), pulse on time (Pon), pulse off time (Poff), and gap voltage (GV) on responses like material removal rate (MRR) and surface roughness (SR) using Taguchi technique on the novel Al7010/2%B4C/2%BN hybrid metal matrix nanocomposite (HMMNC) manufactured through ultrasonic assisted stir casting (UASC) route. The various experiments were planned and carried out L16 orthogonal array and regression equations were established by using Analysis of variance (ANOVA) to examine the impact of pulse factors. The outcomes exposed that discharge current greatest effect factor on MRR and SR was found with % contribution of 82.07% and 86.86%. It is also identified that the optimum level conditions of pulse factors for MRR and SR is A4B4C1D1 and A1B1C4D4. The outcomes were further determined by utilizing confirmatory experiment. The machined surface morphology was observed through Scanning electron microscope (SEM).

Effect of TiO2 inoculants on the wear conduct of the aluminium AA 6061/red mud high performance hybrid composite

The current work focuses on the manufacturing of aluminium AA 6061 composites and its tribological characterization. This is achieved by reinforcing the matrix with red mud. However, the uniform dispersion of red mud requires ultrasonic assisted stir casting and the use of optimum wt.% of TiO2 inoculants. In this regard, the composition of red mud is fixed at 2 wt.%, since the addition of red mud beyond 2 wt.% results in the agglomeration, while the wt.% of TiO2 inoculants is varied from 2 wt.% to 6 wt.%. The wear tests are conducted as per the L9- Orthogonal Array (OA) for a load range of 10 N to 30 N, sliding distance of 500 m to 2500 m, disk rotation speed of 200 RPM to 600 RPM. The regression coefficients are more than 0.9 and close to unity and the error between the experimental outcomes and statistical values are within the tolerance band. The SWR and COF is minimized for 2 wt.% of red mud, 4 wt.% of TiO2, beyond which there is a slight increase in the wear of the composites attributed to the agglomeration of the reinforcments in certain localized regions and the presence of voids in other regions.

Empirical Modelling and Multi-Objective Optimisation of Laser Micro Machining on Magnesium Alloy AS21-SiC Metal Matrix Composite

Micromachining techniques are now being used more frequently as a result of miniaturization. This technique has been supported by the requirement for material processing at an affordable cost and microatomic resolution in numerous sectors. Laser micromachining is a precise, non-contact method of machining that is used to create tiny, up to 500 m, components. The small elemental areas are the focus of laser ablation, which helps absorb a high amount of energy. In this micro-machining, metal removal rate and surface finish are represented by the deepness of the groove and the height of the recast layer. While machining, a layer called a recast layer forms on the work piece surface as a result of the tremendous heat generated, and this layer is damaging to the component's surface quality. For accurate applications, the recast layer must be as tiny as possible. As a result, the objective functions are the height of the recast layer and the deepness of the groove. Experiments designed by the DOE are used to generate empirical models. For each experimental run present in the matrix, the specified input parameter combination is set and the work piece is machined accordingly. The response surface methodology based on mathematical modeling and analysis of the machining properties of a pulsed Nd: YAG laser during micro-grooving operation on a work piece of Magnesium Silicon Alloy metal matrix composite is the focus of this research study. Initially, magnesium alloy AS21-SiC metal matrix composites are manufactured with Ultrasonic pro assisted stir casting. For the machined samples, the deepness of the groove and the height of recast layer will be measured by an optical measuring microscope. Consequently, the measured data is used by the GP to develop the mathematical models. In this work, an efficient GA-based genetic algorithm (NSGA-II) is applied to obtain the optimal parameters. As the chosen objectives are conflicting in nature, the problem is formulated as a multi-objective optimization problem.

Experimental investigation on the two body abrasive wear of AA6061-SiC-Gr nano and hybrid nanocomposites

Aluminium based hybrid nanocomposites can be employed in many applications owing to their desirable traits. Depending on the constituents of the hybrid metal matrix composites, they must be tested for their wear performance since there is a high chance that these materials will experience rapid wear. Determining the tribological behaviour of AA6061/ 2 wt. % SiCp nanocomposite and AA6061/2wt. % SiCp/2 wt. % graphite hybrid nanocomposite is the prime objective of this study. With AA6061 as the metal matrix and nano sized silicon carbide, graphite particles as primary and secondary reinforcements respectively, all the composite samples have been fabricated using ultrasonic assisted stir casting. Evaluation of the wear behaviour of the aforementioned materials is done using the two body abrasive wear tests conducted on a pin-on-disc apparatus. Wear coefficients and friction coefficients have been computed and were also analyzed with respect to various parameters. Additionally, wear mechanisms involved were deciphered and subsequently, wear maps have been developed for all the samples. The sample consisting 2 wt. % SiC and 2 wt. % graphite was found to have excellent wear resistance among all. Additionally, coefficient of friction was the lowest for the aforementioned sample itself.

Machinability Study on AA6061/2 SiC / Graphite Hybrid Nanocomposites Fabricated through Ultrasonic Assisted Stir Casting

Aluminium-based hybrid metal matrix nanocomposites (AA-HMNCs) have numerous applications due to their higher strength-to-weight ratio and good mechanical and tribological properties. However, the machinability aspect of these materials must be carefully explored before employing them in various engineering applications. The present study involves the fabrication of AA6061/2 wt.% SiC/x wt.% graphite (x= 1, 2, 3) hybrid nanocomposites and subsequently subjecting them to machinability investigation. All the hybrid nanocomposite samples are fabricated through ultrasonic assisted stir casting technique. The effect of machining parameters and graphite content of the sample on cutting force and surface roughness is discussed based on experimental data. Experiments are performed based on the central composite design of response surface methodology, and the corresponding output responses are recorded. ANOVA analysis revealed that the graphite content has the highest authority over surface roughness and cutting force. High cutting speeds accompanied by low feed and depth of cut have resulted in reduced cutting forces and better surface finish. Chip morphology studies have also subsequently indicated better machinability with increased graphite content.

Influence of SiC/TiB2 Particles Addition on Corrosion Behavior of As-Cast Zn-Al-Cu Alloy Hybrid Composites

In this work, the silicon carbide (SiC) and titanium diboride (TiB2) reinforced as-cast Zn-Al-Cu alloy-based hybrid composites were produced with ultrasonic-assisted stir casting. The corrosion behavior of as-cast Zn-Al-Cu/TiB2/SiC hybrid composites with varying 0, 5, 10, and 15 weight percent of SiC + TiB2 particulates in Zn-Al-Cu matrix alloy was investigated in this study, The effect of additional reinforcements content on the corrosion behavior of hybrid composites with respect to Zn-Al-Cu alloy was investigated. The corrosion rate of hybrid composites was taken by using potentiodynamic polarization equipment (with 3.5 wt.% NaCl solution). The potentiodynamic polarization test findings showed that the hybrid composites’ uniform and localized corrosion resistances were enhanced by the addition of dual reinforcements. As the weight fraction of the SiC/TiB2 reinforcement increases, weak microgalvanic cells that form between the constituent phases of the fabricated as-cast Zn-Al-Cu hybrid composites weaken, improving their resistance to uniform and localized corrosion. The results revealed that the corrosion rate values were reduced to 28.88% at 15% of reinforcement when compared to the base alloy.

Experimental investigation on mechanical behavior of as cast Zn-Al-Cu/SiC/TiB2 hybrid metal matrix composite by ultrasonic assisted stir casting technique

Now a days, the Zn-Al-Cu alloy-based composites have great impact on modern trends for bearing applications because of its reliable mechanical performance. In this paper the mechanical characteristics of as cast Zn-Al-Cu alloy-based hybrid metal matrix composites have been investigated, as well as the influence of reinforcements Silicon Carbide (SiC) and Titanium Diboride (TiB2) on the composite. The ultrasonic assisted stir casting technique has been adopted for fabricating the composites with the addition of dual reinforcements like 5 wt% of SiC as constant and by varying the wt% of TiB2 as 0 wt%, 5 wt% and 10 wt%. The ceramic particles SiC and TiB2 are taken with 20 and 30 microns in size. The ASTM standards were used to conduct the different tests, and the findings demonstrate the significance of adding reinforcements to alloy and also noticeable increase in mechanical performance in terms of hardness, tensile strength, young’s modulus and impact strength. As cast Zn-Al-Cu/5 wt.% of SiC/10 wt.% of TiB2 hybrid composite gives the minimum density as 4.79 g cc−1 and maximum hardness as 156Hv.