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Article
Publication date: 20 June 2008

Abdul Maleque and Rezaul Karim

The aim is to study the tribological behavior of dual particle size (DPS) and triple particle size (TPS) SiC reinforced aluminum alloy‐based metal matrix composites – MMCs (Al/SiCp

Abstract

Purpose

The aim is to study the tribological behavior of dual particle size (DPS) and triple particle size (TPS) SiC reinforced aluminum alloy‐based metal matrix composites – MMCs (Al/SiCp MMC).

Design/methodology/approach

Al‐MMCs with DPS and TPS of SiC were prepared using 20 wt% SiC and developed using stir‐casting process. The TPS composite consist of three different sizes of SiC and DPS composite consist of two different sizes of SiC. The tribological test was carried out using a pin‐on‐disc type tribo‐test machine under dry sliding condition.

Findings

The TPS composite exhibited better wear resistance properties compared to DPS composite. It is anticipated that when a composite is integrated with small, intermediate and large SiC particle sizes (which is known as TPS) within the same composite could be an effective method of optimizing the wear resistance properties of the developed material.

Practical implications

This study provides a way to enhance the tribological behavior of automotive tribo‐components such as brake rotor, piston, cylinder, etc.

Originality/value

This investigation compares the tribological behavior of DPS and TPS SiC reinforced aluminum MMCs.

Details

Industrial Lubrication and Tribology, vol. 60 no. 4
Type: Research Article
ISSN: 0036-8792

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: 9 February 2015

Necat Altinkök, Ferit Ficici and Aslan Coban

The purpose of this study is to optimize input parameters of particle size and applied load to determine minimum weight loss and friction coefficient for Al2O3/SiC…

Abstract

Purpose

The purpose of this study is to optimize input parameters of particle size and applied load to determine minimum weight loss and friction coefficient for Al2O3/SiC particles-reinforced hybrid composites by using Taguchi’s design methodology.

Design/methodology/approach

The experimental results demonstrate that the applied size is the major parameter influencing the weight loss for all samples, followed by particle size. The applied load, however, was found to have a negligible effect on the friction coefficient. Moreover, the optimal combination of the testing parameters was predicted. The predicted weight loss and friction coefficient for all the test samples were found to lie close to those of the experimentally observed ones.

Findings

The optimum levels of the control factors to obtain better weight loss and friction coefficient were A8 (particle size, 60 μm) and B1 (applied load, 20 N), respectively. Taguchi’s orthogonal design was developed to predict the quality characteristics (weight loss and friction coefficient) within the selected range of process parameters (particle size and applied load). The results were validated through ANOVA.

Originality/value

Firstly, hybrid MMCs ceramic powders were produced and then mechanical tests and optimization were performed.

Details

Industrial Lubrication and Tribology, vol. 67 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 22 September 2023

Rajesh Kumar Bhushan

The purpose of this paper is to examine the quality of the turned surface. The quality of the surface produced depends on the nature of the chips, which are produced while turning…

Abstract

Purpose

The purpose of this paper is to examine the quality of the turned surface. The quality of the surface produced depends on the nature of the chips, which are produced while turning metal matrix composites. This quality is a function of the machining parameters, tool material, tool configuration and elements of the composites.

Design/methodology/approach

In this study, the turning of AA7075/15 wt.% SiC (particle size 20–40 µm) composites is investigated. Thirty experiments were conducted, and the chip-formation mechanism in turning AA7075/SiCp composites at various combinations of cutting speeds, feed and depth of cuts was studied.

Findings

It is observed from the response surface methodology-based experimentation that in turning of coarser reinforcement (particle size 20–40 µm) composites, total gross fracture occurs. This causes small slices of chips and a higher shear plane angle. The nature of chips produced at various combinations of cutting speeds, feed and depth of cuts is different. The chips generated were segmented, spiral in cylindrical form, connected C type, chips with saw tooth, curled chips, washer C type chips, half-curved segmented chips and small-radii segmented chips.

Originality/value

The novelty of this research is that, so far, very little work has been published on the detailed analysis of chips produced during turning of AA7075/15 wt.% SiC (particle size 20–40 µm) composites.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 10
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 14 December 2023

Adem Karci, Veysel Erturun, Eşref Çakir and Yakup Çam

This study aims to investigate the fatigue crack propagation behavior of SiC particle-reinforced 2124 Al alloy composites under constant amplitude axial loading at a stress ratio…

Abstract

Purpose

This study aims to investigate the fatigue crack propagation behavior of SiC particle-reinforced 2124 Al alloy composites under constant amplitude axial loading at a stress ratio of R = 0.1. For this purpose, it is performed experiments and comparatively analyze the results by producing 5, 10, 15 Vol.% SiCp-reinforced composites and unreinforced 2124 Al alloy billets with powder metallurgy (PM) production technique.

Design/methodology/approach

With the PM production technique, SiCp-reinforced composite and unreinforced 2124 Al alloy billets were produced at 5%, 10%, 15% volume ratios. After the produced billets were extruded and 5 mm thick plates were formed, tensile and fatigue crack propagation compact tensile (CT) samples were prepared. Optical microscope examinations were carried out to determine the microstructural properties of billet and samples. To determine the SiC particle–matrix interactions due to the composite microstructure, unlike the Al alloy, which affects the crack initiation life and crack propagation rate, detailed scanning electron microscopy (SEM) studies have been carried out.

Findings

Optical microscope examinations for the determination of the microstructural properties of billet and samples showed that although SiC particles were rarely clustered in the Al alloy matrix, they were generally homogeneously dispersed. Fatigue crack propagation rates were determined experimentally. While the highest crack initiation resistance was achieved at 5% SiC volume ratio, the slowest crack propagation rate in the stable crack propagation region was found in the unreinforced 2124 Al alloy. At volume ratios greater than 5%, the number of crack initiation cycles decreases and the propagation rate increases.

Originality/value

As a requirement of damage tolerance design, the fatigue crack propagation rate and fatigue behavior of materials to be used in high-tech vehicles such as aircraft structural parts should be well characterized. Therefore, safer use of these materials in critical structural parts becomes widespread. In this study, besides measuring fatigue crack propagation rates, the mechanisms causing crack acceleration or deceleration were determined by applying detailed SEM examinations.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 2
Type: Research Article
ISSN: 1748-8842

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 in…

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: 14 September 2011

P. Zak, J. Lelito, J. Suchy, W. Krajewski, K. Haberl and P. Schumacher

The aim of this paper was to determine fitting parameters in grain density of the magnesium primary phase function in AZ91/SiC composite heterogeneous nucleation model. Nucleation…

Abstract

The aim of this paper was to determine fitting parameters in grain density of the magnesium primary phase function in AZ91/SiC composite heterogeneous nucleation model. Nucleation models have parameters, which exact values are usually not known and sometimes even their physical meaning is under discussion. Those parameters can be obtained after statistical analyze of the experimental data. Specimens of fourteen different composites were prepared. The matrix of the composite was AZ91 and the reinforcement was SiC particles. The specimens differs in SiC particles size (10 μm, 40 μm, 76 μm) and content (0 wt.%, 0.1 wt.%, 0.5 wt.%, 2 wt.%, 3.5 wt.%). They were taken from the region near to the thermocouple, to analyze the undercooling for different composites and its influence on the grain size. The specimens were polished and etched. The mean grain size for each specimen was measured. Specific undercooling for each composite was found from characteristic points on cooling rate curve. Microstructure and thermal analyze gave set of values that connect SiC particles content, their size and alloy undercooling with grain size. Those values were used to approximate nucleation model adjustment parameters. Obtained model can be very useful in modelling composites microstructure.

Details

World Journal of Engineering, vol. 8 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 11 August 2022

Royal Madan and Shubhankar Bhowmick

The purpose of this study is to investigate the performance of disks that can be increased by functionally grading the disk in the radial direction; there are several but distinct…

Abstract

Purpose

The purpose of this study is to investigate the performance of disks that can be increased by functionally grading the disk in the radial direction; there are several but distinct categories of literature that pertain to the fabrication of disk in the thickness direction, but to the best of the authors’ knowledge, no study has been conducted yet, in which gradient composition changes radially.

Design/methodology/approach

A powder metallurgy technique was used for the fabrication of Al-SiC-based, three-and five-layered functionally graded (FG) disk. The variation of volume fraction of reinforcement particles (SiC) in a disk changes radially. Finite element analysis has been performed to investigate stress distribution in a layered disk.

Findings

The microstructural investigation was carried out under an optical microscope and scanning electron microscopy integrated with EDS, confirming a uniform distribution of SiC in the matrix (Al). Interface microstructure indicates a successful fabrication of FG material because the transition is uniform in the graded layer without any development of crack or void at the interface. The grain size in the layers decreases with the addition of SiC particles. Additionally, the disk hardness increases as the SiC composition in the layer increases.

Practical implications

An FG disk can be used in a wide range of machinery, from power transmission assemblies to energy storage devices (e.g. flywheel, gears, rotors and disk brake).

Originality/value

The proposed powder metallurgy technique could be used in industries for the fabrication of simple to complicated geometries with FG properties.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 June 1997

Saher Shawki and Z. Abdel Hamid

Electrodeposited Ni‐P composite coatings incorporating a variety of inorganic particles were obtained from Watt’s nickel bath containing sodium hypophosphite. The mechanism of…

Abstract

Electrodeposited Ni‐P composite coatings incorporating a variety of inorganic particles were obtained from Watt’s nickel bath containing sodium hypophosphite. The mechanism of co‐deposition of various particles (SiC, Al2O3, quartz and sand) was studied in view of the electro‐kinetic charge characterizing the solid particles. Means to improve the mobility of the particles in the plating solution were investigated using sodium oleate as surface active agent. The purpose was to increase particle content in the coating to attain high hardness values. Special attention was given to the deposition process using SiC particles. The surface morphology, hardness and wear resistance of the composite coatings were determined. Hardness values were maximized by simple heat treatment in air atmosphere which led to the precipitation of the hard Ni3P phase. Sound, coherent and high wear resistance coatings could be produced.

Details

Anti-Corrosion Methods and Materials, vol. 44 no. 3
Type: Research Article
ISSN: 0003-5599

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 manufactured using…

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

1 – 10 of 699