Compo Casting Method Research Articles

Influence of cenosphere reinforcement on microstructure, microhardness, and corrosion behavior of Al5052 alloy matrix composite produced by compo casting method

The study investigates AA5052alloy matrix composite (MMC) with varying cenosphere particle percentages. Compo-casting integrated cenosphere fly ash particles (2, 4 and 6) wt% into the alloy, improving distribution and wettability. Microhardness increased with higher reinforcement, peaking at 87 Hv with 6% addition. Corrosion resistance in 3.5 wt% NaCl solution showed improved values compared to the base alloy with lowest corrosion rate of 0.144 mmpy for the composite with 6% reinforcement. The study highlights importance of cenosphere reinforcement in enhancing microstructure, hardness, and corrosion resistance in AA5052 MMCs.

Indentation Size Effect of Composite A356 + 6%FA Subjected to ECAP

In this study, metal matrix-based composite (MMC) was subjected to Equal Chanel Angular Pressing (ECAP) in several passes to determine the influence of deformation on the hardness of the samples. Composite based on A356 aluminum alloy and reinforced with Fly Ash (FA) particles was obtained by the compo casting method. The microstructural analyses and microhardness measurements were performed on the cast and pressed samples. Vickers hardness measurement of composite samples was performed with different indentation load sizes: HV0.02, HV0.05, HV0.1 and HV0.2. Results showed that hardness increases after each ECAP pass. The lowest hardness value of 42 (HV0.02) as well as the lowest arithmetical mean value of 46 (HV0.2) was measured at the cast composite. The greatest composite hardness of 107 (HV0.1) and the highest arithmetical mean value of 94 (HV0.1) was measured at the three-time pressed sample. The mathematical model named Meyer’s law was used for data analysis. In the cast sample, a decrease in hardness was detected with increasing indentation load, termed Indentation Size Effect (ISE), was confirmed with Meyers index n = 1.9112 < 2. Pressed samples showed opposite behavior—an increase in hardness with increasing indentation load—where Meyers index n > 2 indicated Reverse Indentation Size Effect (RISE). For all samples, a high coefficient of determination R2 > 0.99 confirmed that Meyer’s law described this phenomenon well.

Investigation on mechanical and tribological properties of AA6061/Gr composites for solar header pipes

Solar header pipes desire light weight material with extensive mechanical and tribological property at high temperature. In this research work, an attempt was made to reinforce AA6061 aluminium alloy with Graphite particles through Stir Casting (SC) and Compo Casting (CC) technique for solar header pipes. The uniform dispersion of reinforcing particles over the matrix was confirmed through Scanning Electron Microscope (SEM). The tensile, hardness and wear experiments were performed on composites at elevated temperature. The wear experimental runs were designed using Taguchi mixed orthogonal array by varying temperature, applied load, sliding velocity, sliding distance and reinforcing weight percentage. The composites produced through CC method exhibit 3.8% and 2.7% higher hardness and tensile strength in comparison with SC. At elevated temperature of 300 C, the composites exhibit better wear resistance owing to the formation of Mechanical Mixed Layer (MML). The wear rate of composites at elevated temperature was three times higher than the room temperature owing to reduction in density and deformation of material. ANOVA table reveals that the most influencing process parameters was temperature followed by the load and percentage reinforcement. The worn surface morphology was analyzed using SEM. Because of the improved dispersion of reinforced particles, the composites generated by CC have higher mechanical and tribological qualities at elevated temperatures, and are considered as an alternative material for solar header pipes.

Solid particle erosion resistance of Al alloy and Al alloy-fly ash composite subjected to equal-channel angular pressing

This paper describes the influence of deformation by equal-channel angular pressing (ECAP) on the solid particle erosion resistance of the AlSi7Mg0.3 alloy and AlSi7Mg0.3 based composite material reinforced with the addition of 4 % of fly ash (FA) particles. Both, alloy and composite samples were produced using the compo-casting method. The samples have been subjected to ECAP in multiple passes with the rotation of samples around the vertical axis for the angle of 90° after each pass. Particles of silicon carbide (SiC) have been used as erodent while their impact angle was varied (30° and 90°). Observed samples of AlSi7Mg0.3 alloy generally showed higher wear resistance at 90° angle where material fatigue predominates, than at a 30° angle where abrasion-related phenomena predominate. On the other hand, AlSi7Mg0.3 based composite material exhibited erosion wear at 30° angle less than at 90° angle after one ECAP pass. Evaluation of the erosion resistance has been made based on mass and volume loss. After two passes of ECAP, the matrix structure of the AlSi7Mg0.3 based composite material, as well as that of the AlSi7Mg0.3 alloy was improved from the aspect of erosion resistance.

A systematic overview on fabrication aspects and methods of aluminum metal matrix composites

Aluminum metal matrix composites (AlMMCs) have been incredibly popular in different industries because of their well-known properties as good formability and high castability. AlMMCs have exceptionally good mechanical characteristics and fairly low costs, so they are a very feasible choice for various applications. The popular materials for specialized applications are primarily AlMMCs, as their characteristics can be customized by the selection of reinforcement materials according to requirements. AlMMCs are preferred and extensively used in industries as well as other domestic applications. The versatility of such composites is that their mechanical properties can effectively be configured in any manner by choosing their composition of reinforcing and matrix materials, but AlMMCs have significant weaknesses in terms of production expense. Research is required to build AlMMCs that are cost-effective and work on high-temperature industrial applications. The key goal is therefore to develop a cost-effective manufacturing process. The emphasis of this paper is a study on effective and popular methods for the fabrication of AlMMCs, including liquid, solid fabrication routes such as the compo-casting method, stir-casting, squeeze-casting and powder metallurgy. This paper discusses these production processes. This article aims to include a literature analysis of the current basic approaches utilized to produce AlMMCs and their technological applications.

Evaluation of Fracture Mechanisms in Al-Si Metal Matrix Nanocomposites Produced by Three Methods of Gravity Sand Casting, Squeeze Casting and Compo Casting in Semi-Solid State

Magnetic stirring is considered to be the most useful stirring method in semi-solid casting processes which doesn’t have the restrictions of the mechanical stirring. In this research, fracture mechanisms of aluminum-Al2O3 nanocomposites produced by three methods of gravity sand casting, squeeze casting and compo casting in semi-solid state using electromagnetic stirring were studied and discussed. For this purpose, microstructure and fracture surfaces obtained from broken tensile test samples were analyzed using optical and scanning electron microscopies. On the fracture surfaces of all the samples, dimples were observed, which are the sign of ductile fracture. It was revealed that the dimples on the samples produced by the compo casting method are smaller, more spherical and uniformly distributed in the metal matrix in comparison with the ones from sand and squeeze casting. It also investigated that on the fracture surfaces of compo casting samples less cleavage planes, dendritic fracture and particles agglomeration were observed in comparison with the ones from the sand and squeeze casting processes.

Mechanical behaviour of As-Cast and Heat-Treated: AA2024 Alloy Silicon Carbide-Al2O3 Hybrid Composites

This paper reports on the mechanical properties of as-cast and heat-treated AA2024 alloy hybrid composites reinforced with SiC/ Al2O3 from 1 to 5 wt %. The hybrid composites were fabricated using the Compocasting method, in which short SiC/Al2O3 were introduced into the vortex created in the molten alloy through an impeller rotated at 500 rpm. The molten mass was thoroughly stirred and poured into permanent molds and squeezed under pressure. The specimens were heat treated at 575°C for 1, 2, 3, and 4 h. The tests on the as-cast hybrid composites revealed that as the glass content in the hybrid composites was increased, the ultimate tensile strength (UTS), compressive strength, and hardness of the composite increased, while the ductility and impact strength were decreased. Heat treatment was found to improve significantly the ductility, compressive strength, and impact strength, while the hardness and UTS were reduced. This paper discusses the behavior of these hybrid composites.

A study on Corrosion Behavior of AA5083 – MWCNT Reinforced Composite

Abstract The AA5083 (Aluminium alloy) and AA5083 – MWCNT (1.5 wt %) was fabricated using compo-casting method to study the corrosion behavior. Field-emission scanning electron microscope, X-RD and EDS was performed to check the dispersion of MWCNT into the developed composite. Corrosion behavior of aluminium alloy in the absence and presence of MWCNT reinforced composites in 1 N sodium hydroxide was studied by conventional weight loss method, electrochemical impedance spectroscopy and potentiodynamic polarisation methods. Results showed that reinforced alloy have lower corrosion rates compared to unreinforced alloy. The experiments were performed by changing immersion time from 1- 6 hours at ambient temperatures. The results show that at ambient temperature the AA5083 – MWCNT have better corrosion resistance than the AA5083 matrix material. Atomic force microscopy was performed to understand the corrosion mechanism of the MWCNT reinforced composite.

Improved Mechanical Properties of AA5083 Reinforced with Multiwall Carbon Nanotubes for Automobile Applications

Aluminium alloys are widely used in automobile applications due to their good mechanical, corrosion and wear resistance properties. This work mainly focuses on the enhancement of mechanical properties of Aluminium alloy AA5083/MWCNT composites using a semi-solid state route (compo-casting method) and compare with the conventional AA5083 alloy. AA5083 and MWCNT microstructures were examined using field emission scanning electron microscope and energy-dispersive X-ray spectroscopy analysis. The experimental results showed an enhancement in the ultimate tensile strength and yield strength for the MWCNT reinforced composite compared to the corresponding values of AA5083. The Brinell Hardness of the MWCNT reinforced composite was better than the conventional AA5083.

Study of mechanical and wear characteristics of AL380 composite fabricated by introducing B4C using compo casting method

In the present work, Al380 Al alloy and B4C metal matrix composite was fabricated with different weight fractions (1%,2% and 3%) using compo-casting method. The wear properties of fabricated composite is tested by pin on disc apparatus. On different loads of 30N,60N and 90N the wear tests are performed. The mechanical properties of hardness and tensile strength are performed on brinell’s hardness apparatus and Ultimate tensile machine. The study of homogeneous distribution of B4C particles were examined by scanning electron microscope (SEM) in the composites. The result shows that the Al380 Al alloy reinforced with B4C particles, that composite improves the mechanical properties and wear rate. Increasing of wear rate with the increase in B4C particles in composites. Using Opti- cal microscope, the study of worn surfaces of pins were analyzed.

Study on Tribological Behaviour of Al/SiC/MoS2 Hybrid Metal Matrix Composites in High Temperature Environmental Condition

The current study investigates the tribological behaviour of aluminium hybrid composite reinforced with SiC and MoS2 at various temperature environments. The hybrid metal matrix composites have been fabricated through compo casting method by reinforcing different sizes of SiC (10, 20, 40 μm) at various weight fractions (5%, 10% & 15%) with 5059 aluminium alloy, meanwhile the addition of Molybdenum disulphide (MoS2) is fixed at 2%. Tribological behaviour of composites was evaluated based on wear loss and friction coefficient by using pin on disc apparatus. Along with particle size and weight percentage of SiC, load, sliding velocity, sliding distance and temperature were considered as process parameters and L27 orthogonal array was selected to perform the experiments. Through Taguchi and Analysis of Variance (ANOVA) method optimum sliding condition for reduced wear loss and the significance of each parameter on wear behaviour of the composite were identified. Temperature and load predominantly affects the tribological behaviour of aluminium hybrid composite. It was found that the wear resistance is high when smaller particles were reinforced at maximum percentage (15%) and the results were supported with worn surface SEM images.

Optimization of electrical discharge machining process parameters for Al6061/cenosphere composite using grey-based hybrid approach

Fly ash has congregated considerable attention as a potential reinforcement for aluminum matrix composites (AMCs) to enhance selective properties and reduce the cost of fabrication. However, poor machinability of such AMCs limits their application. The present study focuses on the preparation of cenosphere fly ash reinforced Al6061 alloys by compo casting method. X-ray diffraction analysis of the prepared AMCs exposes the presence of cenosphere particles without any formation of other intermetallic compounds. In this study, electrical discharge machining (EDM) was engaged to examine the machinability of the prepared metal matrix composite (MMCs). The measured performance characteristics for the various combinations of input process parameters were considered to be MRR, EWR and SR. Face centered central composite design (CCD) of response surface method (RSM) was employed to design the number of experimental trials required and a hybrid approach of grey-based response surface methodology (GRSM) was imposed for predicting the optimal combination of processing parameter in EDM process. Generous improvement was observed in the performance characteristics obtained by employing both the optimal setting of machining parameters. The optical 3D surface profile graphs of the ED machined surface also revealed the improvement in surface quality and texture employing the optimal processing conditions proposed by hybrid GRSM approach.

Fabrication Method of Aluminum Matrix Composite (AMCs): A Review

Aluminium matrix composites (AMCs) are increasingly become attractive materials for advanced applications including aerospace and automotive applications because of their properties can be tailored through the addition of selected reinforcements. On viewing from both scientific and technological aspects, their excellent mechanical properties and relatively low production cost makes them a very viable candidate for a variety of applications. This paper focused on the suitable and common methods used to fabricate the AMCs such as powder metallurgy, stir-casting, squeeze casting and compo-casting method. The advantages and disadvantages of those fabrication methods are discovered through this paper.

New Compo-Casting Method of Ceramics Inserted Cast Iron Reducing Thermal Stress

The compo-casting of ceramics by cast iron is expected to be one of the useful casting process that can expand the application fields of cast iron. The largest problem in compo-casting method is cracking caused by thermal shock. Although this cracking can be prevented by reducing the thermal stress by preheating ceramics, the necessary preheating temperature is high and its precise control is difficult at practical foundries. In this study, we tried to estimate numerically the critical preheating temperature of ceramics using the thermal stress analysis during transient thermal conduction and the Newman’s diagram. We also found that the preheating of ceramics to reduce thermal stress can be replaced with placing an appropriate cast iron covers around the ceramics. We describe new compo-casting method that needs no preheating of ceramics and proved the usefulness experimentally.

DRY SLIDING WEAR BEHAVIOUR OF FLYASH REINFORCED ZA-27 ALLOY BASED METAL MATRIX COMPOSITES

In the present investigation, an attempt has been made to evaluate the wear rate of ZA-27 alloy composites reinforced with fly ash particles from 1 to 3 wt% in steps of 1 wt%. The compo-casting method has been used to fabricate the composites using Raichur fly ash of average size 3-5 microns. The wear specimens are tested under dry conditions using a pin-on-disc sliding wear testing machine with wear loads of 20-120 N in steps of 20 N, and the sliding distances in the range of 0.5 km to 2.5 km. The results indicate that the wear rate of the composites is less than that of the matrix alloy and it further decreases with the increase in fly ash content. However, the material loss in terms of wear rate and wear volume increases with the increase in load and sliding distance, both in the cases of composites and the matrix alloy. An increase in the applied load increases the wear severity by changing the wear mechanism from abrasion to particle-cracking induced delamination wear. It is found that with the increase in fly ash content, the wear resistance increases monotonically. The observations have been explained using scanning electron microscope (SEM) analysis of the worn surfaces of the composites.

New Compo-Casting Method of Ceramics Inserted Cast Iron Reducing Thermal Stress

The compo-casting of ceramics by cast iron is expected to be one of the useful casting process that can expand the application fields of cast iron. The largest problem in compo-casting method is cracking caused by thermal shock. Although this cracking can be prevented by reducing the thermal stress by preheating ceramics, the necessary preheating temperature is high and its precise control is difficult at practical foundries. In this study, we tried to estimate numerically the critical preheating temperature of ceramics using the thermal stress analysis during transient thermal conduction and the Newman’s diagram. We also found that the preheating of ceramics to reduce thermal stress can be replaced with placing an appropriate cast iron covers around the ceramics. We describe new compo-casting method that needs no preheating of ceramics and proved the usefulness experimentally.

Mechanical Properties of As-Cast and Heat-Treated ZA-27 Alloy/Short Glass Fiber Composites

This paper reports on the mechanical properties of as-cast and heat-treated ZA-27 alloy composites reinforced with glass fibers from 1 to 5 wt%. The composites were fabricated using the Compocasting method, in which short glass fibers were introduced into the vortex created in the molten alloy through an impeller rotated at 500 rpm. The molten mass was thoroughly stirred and poured into permanent molds and squeezed under pressure. The specimens were heat treated at 320 °C for 1, 2,3, and 4 h. The tests on the as-cast composites revealed that as the glass content in the composites was increased, the ultimate tensile strength (UTS), compressive strength, and hardness of the composite increased, while the ductility and impact strength were decreased. Heat treatment was found to improve significantly the ductility, compressive strength, and impact strength, while the hardness and UTS were reduced. This paper discusses the behavior of these composites.