Effect of Addition of Fine SiC Particles on the Dry Sliding Wear Behaviour of Extruded 2014 Al-Alloy

Rupa Dasgupta,S Das,A K Jha

doi:10.5402/2013/648524

Abstract

Composites of 2014 alloy made by dispersing 10 vol.% of fine (20–50 µm) SiC particles using vortex method ensuring uniform distribution of SiC particles in the matrix have shown uniform distribution of SiC particles. Mechanical properties of the composites have also registered an improvement over the alloy. In an attempt to further improve the properties, the composites were subjected to hot extrusion of cylindrical rods along with the alloys under similar experimental conditions. A temperature range of 300–350°C and an extrusion ratio of 10 : 1 were maintained during the process. The extruded samples were compared for their mechanical properties, and improvement was noted. The mechanism of material failure from fractographic studies showed difference in behaviour between the alloy and composite. Dry sliding wear studies carried out on extruded specimens exhibited improved wear behaviour in composites over alloys as measured by volume loss and wear rate. Wear mechanism was studied from the worn surface and correlated with the wear performance. It was observed that the presence of SiC particles reduces the tendency of delamination and thus material removal from the wear surface.

Highlights

Researchers have repeatedly demonstrated on a laboratory scale, attractive properties in aluminium-based metal matrix composites with SiC dispersoids. e property improvements relate to microstructural, mechanical properties such as speci c modulus, strength, and wear resistance, in addition to a service temperature capability in selected aluminium-based composites with selected second phase dispersoids
Challenges of extruding Al-based MMCs have been overcome by the authors in the past and optimised conditions for extrusion established [23]. e present paper reports the effect of extrusion under optimised conditions on a 2014 based aluminium alloy and its composite made with 10 vol.% SiC dispersoids and compares the properties, namely, microstructure, mechanical and dry ISRN Tribology (a)
Dry sliding wear of extruded composites shows a marked improvement over extruded alloys under all conditions of load and speed tested over the entire sliding distance tested. e material removal method in the case of alloys consists of rst making groove marks on the surface, as the conditions continue the grooves get deeper and the material forming a layer on the surface being worn, this surface could form a layer somewhat elevated from the specimen and gradually peels off

Summary

Introduction

Researchers have repeatedly demonstrated on a laboratory scale, attractive properties in aluminium-based metal matrix composites with SiC dispersoids. e property improvements relate to microstructural, mechanical properties such as speci c modulus, strength, and wear resistance, in addition to a service temperature capability in selected aluminium-based composites with selected second phase dispersoids. E property improvements relate to microstructural, mechanical properties such as speci c modulus, strength, and wear resistance, in addition to a service temperature capability in selected aluminium-based composites with selected second phase dispersoids. It is an open knowledge for researchers in this eld as to the alloy systems, second phase s nature, volume fraction, and fabrication routes that can exhibit improved performance. Attempts at secondary processing of Al-based MMCs especially through extrusion to deform the materials into desired shapes and re ne the microstructure are being reported substantially [15–22]; the extruded MMCs exhibit uniform reinforced distribution, reduced porosity, ner grain structures, improved mechanical and physical properties, and improved bonding as compared to the cast products. Challenges of extruding Al-based MMCs have been overcome by the authors in the past and optimised conditions for extrusion established [23]. e present paper reports the effect of extrusion under optimised conditions on a 2014 based aluminium alloy and its composite made with 10 vol.% SiC dispersoids and compares the properties, namely, microstructure, mechanical and dry ISRN Tribology (a)

Methods

Results

Conclusion