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Article
Publication date: 16 July 2019

Akhil Khajuria, Modassir Akhtar, Manish Kumar Pandey, Mayur Pratap Singh, Ankush Raina, Raman Bedi and Balbir Singh

AA2014 is a copper-based alloy and is typically used for production of complex machined components, given its better machinability. The purpose of this paper was to study…

Abstract

Purpose

AA2014 is a copper-based alloy and is typically used for production of complex machined components, given its better machinability. The purpose of this paper was to study the effects of variation in weight percentage of ceramic Al2O3 particulates during electrical discharge machining (EDM) of stir cast AA2014 composites. Scanning electron microscopy (SEM) examination was carried out to study characteristics of EDMed surface of Al2O3/AA2014 composites.

Design/methodology/approach

The effect of machining parameters on performance measures during sinker EDM of stir cast Al2O3/AA2014 composites was examined by “one factor at a time” (OFAT) method. The stir cast samples were obtained by using three levels of weight percentage of Al2O3 particulates, i.e. 0 Wt.%, 10 Wt.% and 20 Wt.% with density 1.87 g/cc, 2.35 g/cc and 2.98 g/cc respectively. Machining parameters varied were peak current (1-30 amp), discharge voltage (30-100 V), pulse on time (15-300 µs) and pulse off time (15-450 µs) to study their influence on material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR).

Findings

MRR and SR decreased with an increase in weight percentage of ceramic Al2O3 particulates at the expense of TWR. This was attributed to increased microhardness for reinforced stir cast composites. However, microhardness of EDMed samples at fixed values of machining parameters, i.e. 9 amp current, 60 V voltage, 90 µs pulse off time and 90 µs pulse on time reduced by 58.34, 52.25 and 46.85 per cent for stir cast AA2014, 10 Wt.% Al2O3/AA2014 and 20 Wt.% Al2O3/AA2014, respectively. SEM and quantitative energy dispersive spectroscopy (EDS) analysis revealed ceramic Al2O3 particulate thermal spalling in 20 Wt.% Al2O3/AA2014 composite. This was because of increased particulate weight percentage leading to steep temperature gradients in between layers of base material and heat affected zone.

Originality/value

This work was an essential step to assess the machinability for material design of Al2O3 reinforced aluminium metal matrix composites (AMMCs). Experimental investigation on sinker EDM of high weight fraction of particulates in AA2014, i.e. 10 Wt.% Al2O3 and 20 Wt.% Al2O3, has not been reported in archival literature. The AMMCs were EDMed at variable peak currents, voltages, pulse on and pulse off times. The effects of process parameters on MRR, TWR and SR were analysed with comparisons made to show the effect of Al2O3 particulate contents.

Details

World Journal of Engineering, vol. 16 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 2 August 2021

Anas Islam, Shashi Prakash Dwivedi and Vijay Kumar Dwivedi

This paper aims to extract the Cr from chrome containing leather waste (CCLW) in order to develop composite at optimum casting parameters using RSM technique. Chrome…

Abstract

Purpose

This paper aims to extract the Cr from chrome containing leather waste (CCLW) in order to develop composite at optimum casting parameters using RSM technique. Chrome containing leather wastes (CCLW) is one of the significant cause of pollution that is exhaled by the leather industries. One of the technique to address the problem of pollution that is created by CCLW is to recycle it and produce some fruitful results from it. This will not only minimize the levels of harmful emissions to some extent but also give some befitting results.

Design/methodology/approach

The current work is all about exploring the ways by which CCLW could be used as a reinforcing material with aluminum. In this work, alumina has been used as a secondary reinforcement particle together with CCLW as with the help of stir casting process. The parameters of stir casting have been optimized by using “Response Surface Methodology.”

Findings

To maximize the hardness and tensile strength the values of optimal input casting parameters as found by the experimental results (response surface methodology) are as follows: the pre-heating temperature of collagen and alumina must be 166 °C and 300 °C, respectively, while the wt.% of collagen and alumina present in the matrix must be 2.45% and 5% sequentially 180 s of stirring time.

Originality/value

The hardness of the finally tested composite is 67.12 BHN (approx) which has been enhanced by 52.54% as compared to the base material. Tensile strength of composite also enhanced about 18% with respect to base material developed at the optimum combination of casting parameters.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 28 May 2021

Jiaqi Pan, Xiaoshan Liu, Guoqiu He, Bin Ge, Peiwen Le, Jingquan Li and Zhiqiang Zhou

The purpose of this paper is to understand the effect of particle content, applied load and sliding speed on the tribological properties of A356-SiCP composites…

Abstract

Purpose

The purpose of this paper is to understand the effect of particle content, applied load and sliding speed on the tribological properties of A356-SiCP composites manufactured using a newly developed vacuum stir casting technique.

Design/methodology/approach

A356 alloy reinforced with 10, 15 and 20 vol% SiC particles was prepared by vacuum stir casting. Tribological tests were carried out on block-on-ring tribometer under dry sliding conditions, room temperature. Wear mechanism was investigated by scanning electron microscope and energy dispersion spectrum.

Findings

SiCP is homogeneously dispersed in the matrix. The increase in SiCP content decrease wear rate, but it leads to an increase in coefficient of friction. The wear rate increase and friction coefficient present different variation trends with increasing load. For A356-20%SiCP composite, when the load is less than 10 MPa, wear rate and friction coefficient under sliding speed of 400 rpm are lower than those of 200 rpm. Wear mechanism transition from abrasion, oxidation, delamination, adhesion to plastic flow as load and sliding speed increasing.

Practical implications

Results of this study will help guide the use of A356-SiCP in many automotive products such as brake rotors, brake pads, brake drums and pistons.

Originality/value

There are few paper studies the effect of particle content, applied load and sliding speed on the tribological properties of A356-SiCP composites. Aluminum matrix composites with uniform distribution of reinforcing particles were successfully prepared by using the newly developed vacuum stir casting technique.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 10 May 2021

Ravi Butola, N. Yuvaraj, Ravi Pratap Singh, Lakshay Tyagi and Faim Khan

This study aims to analyse the changes in mechanical and wear performance of aluminium alloy when yttrium oxide particles are incorporated. The microstructures are studied…

Abstract

Purpose

This study aims to analyse the changes in mechanical and wear performance of aluminium alloy when yttrium oxide particles are incorporated. The microstructures are studied to analyse the change in the grain structures. Worn surfaces are observed via scanning electron microscope to study the wear mechanism in detail.

Design/methodology/approach

Stir casting is used to incorporate varying composition of yttrium particles, having an average particle size of 25 micrometer, in aluminium alloy 6063 matrix. Wear testing is carried out by DUCOM manufactured high temperature rotatory tribometer, and an indentation test is used for analysing the microhardness of the fabricated samples.

Findings

Microhardness of the material is increased with the increasing content of particulate addition. With the increasing content of reinforcement, more refined grains are produced. The load is transferred from the matrix to more rigid yttrium oxide particles. These factors contributed to escalated microhardness of the reinforced samples. Particulate addition enhanced the wear performance of the material; this might be attributed to increased microhardness and formation of an oxide layer.

Originality/value

Aluminium composites are finding wide applications in various industries, and there is always a requirement of material with enhanced tribological properties. Yttrium oxide particles exhibit improved mechanical properties, and their interaction with the aluminium matrix has not been studied much in the past. So, in this work, yttrium oxide incorporated aluminium matrix is studied.

Details

World Journal of Engineering, vol. 19 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 16 April 2020

Rajesh Kumar Bhushan

Mechanical properties are highly sensitive to the microstructure, and these are indirectly related to solidification parameters and processing conditions. AA7075 possesses…

Abstract

Purpose

Mechanical properties are highly sensitive to the microstructure, and these are indirectly related to solidification parameters and processing conditions. AA7075 possesses lightweight and excellent properties as structural material which can be optimized with SiCp addition and a good fabrication technique.

Design/methodology/approach

7000 series aluminium alloys exhibit the highest mechanical properties. They are used for high-strength structural applications such as aircraft parts and sporting goods. The desirable properties of these alloys are: low density, high stiffness, specific strength, good wear resistance and creep resistance. The focus of this work is to investigate the microstructure of composites formed by the dispersion of silicon carbide particles (SiC) into AA7075 by stir casting processes. 7075 Al alloy is reinforced with 10 and 15 wt.% SiCp of size 10–20 µm by stir casting process. The composites have been characterized by X-ray diffraction and scanning electron microscopy, differential thermal analysis and electron probe microscopic analysis.

Findings

SiCp distribution and interaction with AA7075 matrix have been studied. AA7075/10 wt.%/SiCp (10–20 µm) and AA7075/15 wt.%/SiCp (10–20 µm) composites microstructure showed excellent SiCp distribution into AA7075 matrix. In addition, no evidence of secondary chemical reactions has been observed in X-ray diffraction and electron probe microscopic analysis.

Originality/value

Little experimental work has been reported so far about effect of addition of 10 and 15 wt.% SiCp of size (10–20 µm) on the microstructure of 7075 Al alloy fabricated by stir casting process. The present investigation has been carried out to study the microstructure and carry out XRD, DTA and EPMA analysis of 7075 Al alloy, 10 and 15 wt.% SiCp of size (10–20 µm) composite and detect the interfacial reactions with the objective to minimize the formation of Al4C3.

Details

International Journal of Structural Integrity, vol. 12 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 24 August 2021

Deepak Sharma and Rajesh Kumar Bhushan

Parts that are to be used in aircraft, satellites, automobiles and ships should have sound microstructure. Components made from AA6082/Si3N4 and AA6082/SiC composites are…

Abstract

Purpose

Parts that are to be used in aircraft, satellites, automobiles and ships should have sound microstructure. Components made from AA6082/Si3N4 and AA6082/SiC composites are in demand from industries. Hence, these components are to be fabricated by suitable technique at the appropriate value of process parameters. The purpose of this paper is Microstructure analysis of AA6082/Si3N4 and AA6082/SiC composites

Design/methodology/approach

AA6082/Si3N4 and AA6082/SiC composites are successfully fabricated using the stir casting process. Their microstructures have been analyzed. This has been done at different magnification. The effect of the addition of Si3N4 and SiC particles in the 6082 aluminum alloy is investigated. Microstructure of AA6082/Si3N4 and AA6082/SiC composites are also compared. Results show that Si3N4 and SiC particles have good wettability with AA6082. These reinforcement particles are homogeneously distributed in the matrix of AA6082.

Findings

There are no adverse effects of reactions in the microstructure of AA6082/Si3N4 and AA6082/SiC composites. There is not much difference between the distribution and interfacial characteristics of Si3N4 and SiC particles. AA6082/Si3N4 and AA6082/SiC composites have good properties. This is high strength at low density. Due to which they become suitable for the aircraft and space industry. So far, SiC, Al2O3 and tungsten carbide have been mostly used as reinforcements with different grades of aluminum alloy.

Originality/value

Not much experimental work is found with Si3N4 and SiC particles as reinforcement with AA6082. The novelty of this research work is that an effort has been made to fabricate AA6082/Si3N4 and AA6082/SiC composites at such values of process parameters, by stir casting process, so that sound and defect free microstructure is obtained. Microstructure of AA6082/Si3N4 and AA6082/SiC composites is also compared, to find which is better.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 28 September 2018

Ambrish Maurya and Pradeep Kumar Jha

This investigation aims to analyze the steel-flux interface level fluctuation because of electromagnetic stirring and its process parameters in a continuous casting billet mold.

Abstract

Purpose

This investigation aims to analyze the steel-flux interface level fluctuation because of electromagnetic stirring and its process parameters in a continuous casting billet mold.

Design/methodology/approach

An un-coupled numerical model for electromagnetic field generation and a coupled numerical model of electromagnetic field and two-phase fluid flow have been developed. The two-phase fluid flow has been modeled using volume of fluid method, in which externally generated time-varying electromagnetic field is coupled and analyzed using magnetohydrodynamic method. Top surface standing wave stability criteria are used to study the criticality of interface stability.

Findings

Results show that application electromagnetic field for stirring increases the interface level fluctuation, specifically at the mold corners and near the submerged entry nozzle. The increase in current intensity and stirrer width barely affect the interface level. However, interface level fluctuation increases considerably with increase in frequency. Using stability criteria, it is found that at 20 Hz frequency, the ratio of height to wavelength of interface wave increases much above the critical value. The iso-surface of the interface level shows that at 20 Hz frequency, mold flux gets entrapped into the liquid steel.

Practical implications

The model may be used during optimization of in-mold electromagnetic stirrer to avoid mold flux entrapment and control the cast quality.

Originality/value

The study of mold level fluctuation in the presence of in-mold electromagnetic stirrer has rarely been reported. The criticality of stirrer process parameters on level fluctuation has not been yet reported. This study lacks in experimental validation; however, the findings will be much useful for the steelmakers to reduce the casting defects.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 28 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 3 July 2017

Ambrish Maurya and Pradeep Kumar Jha

The purpose of present investigation is to analyze the in-mold electromagnetic stirring (M-EMS) process and the effect of stirrer frequency on fluid flow and…

Abstract

Purpose

The purpose of present investigation is to analyze the in-mold electromagnetic stirring (M-EMS) process and the effect of stirrer frequency on fluid flow and solidification in a continuous casting billet caster mold.

Design/methodology/approach

A hybrid approach involving finite element and finite volume method has been used for the study. Finite element model is used to calculate time variable magnetic field, which is further coupled with fluid flow and solidification equations for magneto-hydrodynamic analysis with finite volume model.

Findings

Results show that though superheat given to steel before its entry into the mold is quickly removed, solid shell formation is delayed by the use of M-EMS. Final solid shell thickness, however, is slightly reduced. Increase in frequency is found to increase the magnetic flux density and tangential velocity of liquid steel and decrease in diameter of liquid core.

Practical implications

The work is of great industrial relevance. The model may be used to design industrial setup of in-mold electromagnetic stirrer and process could be analyzed and optimized numerically.

Originality/value

The paper evaluates the influence of M-EMS and its frequency on solidification and flow behavior in the continuous casting mold. The iso-surface temperatures from pouring temperature to liquidus temperature inside the mold have been shown. The findings may be useful for the steelmakers to reduce the defect in continuous casting.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 28 September 2010

M. Kathiresan and T. Sornakumar

Metal matrix composites (MMCs) are engineered materials formed by the combination of metal matrix and reinforcement materials. They have a stiff and hard reinforcing phase…

1356

Abstract

Purpose

Metal matrix composites (MMCs) are engineered materials formed by the combination of metal matrix and reinforcement materials. They have a stiff and hard reinforcing phase in metallic matrix. The matrix includes metals such as aluminum, magnesium, copper and their alloys. The purpose of this paper is to describe the development of an aluminum alloy‐aluminum oxide composite using a new combination of vortex method and pressure die casting technique and the subsequent tribological studies.

Design/methodology/approach

An aluminum alloy‐aluminum oxide composite was developed using vortex method and pressure die casting technique. The aluminum alloy‐1 wt% aluminum oxide was die cast using LM24 aluminum alloy as the matrix material and aluminum oxide particles of average particle size of 16 μm as a reinforcement material. The friction and wear characteristics of the composite were assessed using a pin‐on‐disc set‐up; the test specimen, 8‐mm diameter cylindrical specimens of the composite, was mated against hardened En 36 steel disc of 65 HRC. The tests were conducted with normal loads of 9.8, 29.4 and 49 N and sliding speeds of 3, 4 and 5 m/s for a sliding distance of 5,000 m. The frictional load and the wear were measured at regular intervals of sliding distance.

Findings

The effects of normal load and sliding speed on tribological properties of the MMC pin on sliding with En 36 steel disc were evaluated. The wear rate increases with normal load and sliding speed. The specific wear rate marginally decreases with normal load. The coefficient of friction decreases with normal load and sliding speed. The wear and friction coefficient of the aluminum alloy‐aluminum oxide MMC are lower than the plain aluminum alloy. The wear and coefficient of friction of the entire specimens are lower.

Practical implications

The development of aluminum alloy‐aluminum oxide composite using vortex method and pressure die casting technique will revolutionize the automobile and other industries, since a near net shape at low cost and very good mechanical properties are obtained.

Originality/value

There are few papers available on the development of (or tribological studies of) MMCs including aluminium/aluminium alloy‐ceramic composites developed by combination of vortex method and pressure die casting technique.

Details

Industrial Lubrication and Tribology, vol. 62 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 6 March 2009

Abdul Maleque and Rezaul Karim

The purpose of this paper is to study the wear behavior of as‐cast (AC) and heat treated (HT) triple particle size (TPS) silicon carbide (SiC) reinforced aluminum…

Abstract

Purpose

The purpose of this paper is to study the wear behavior of as‐cast (AC) and heat treated (HT) triple particle size (TPS) silicon carbide (SiC) reinforced aluminum alloy‐based metal matrix composites (SiCp/Al‐MMC).

Design/methodology/approach

Al‐MMCs were prepared using 20 vol.% SiC reinforcement into aluminum metal matrix and developed using a stir casting process. Stir casting is a primary process of composite production whereby the reinforcement ingredient material is incorporated into the molten metal by stirring. The TPS composite consist of SiC of three different sizes viz., coarse, intermediate, and fine. The solution heat treatment was done on AC composite at 540°C for 4 h followed by precipitation treatment. The wear test was carried out using a pin‐on‐disc type tribo‐test machine under dry sliding condition. A mathematical analysis was also done for power factor values based on wear and friction results. The wear morphology of the damaged surface was also studied using optical microscope and scanning electron microscope (SEM) in this investigation.

Findings

The test results showed that HT composite exhibited better wear resistance properties compared to AC composite. It is anticipated that heat treatment could be an effective method of optimizing the wear resistance properties of the developed Al‐MMC material.

Practical implications

This paper provides a way to enhance the wear behavior of automotive tribo‐components such as brake rotor (disc and drum), brake pad, piston cylinder, etc.

Originality/value

This paper compares the wear behavior of AC and HT TPS reinforced Al‐MMC material under dry sliding condition.

Details

Industrial Lubrication and Tribology, vol. 61 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

1 – 10 of over 1000