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Ô³çèêî-õ³ì³÷íà ìåõàí³êà ìàòåð³àë³â. – 2015. – ¹ 4. – Physicochemical Mechanics of Materials

STUDY OF CHARACTERISTICS OF Al + 5 wt.% TiO 2 + 6 wt.% Gr
HYBRID P/M COMPOSITE POWDERS PREPARED
BY BALL MILLING PROCESS

2
1
3
M. RAVICHANDRAN , VS. VIDHYA , V. ANANDAKRISHANAN
1
Department of Mechanical Engineering, Kings College of Engineering, Pudukkottai, India;
2
Department of Chemistry, Chendhuran College of Engineering and Technology, Pudukkottai, India;
3
Department of Production Engineering, National Institute of Technology, Tiruchirappalli,
Tamilnadu, India
This paper is an attempt to understand the characteristics of Al + TiO 2 + Gr hybrid ball
milled composite powders, which is anticipated to have large application in the near future.
Aluminium with titanium dioxide (TiO 2 ) and graphite (Gr) powders was ball milled in
order to yield the composition like: Al + 0% TiO 2 , Al + 5% TiO 2 , Al + 5% TiO 2 + 2% Gr,
Al + 5% TiO 2 + 4% Gr and Al + 5% TiO 2 + 6% Gr. From the X-Ray diffraction analysis
of the milled powders, the grain size, lattice space, lattice constant, stress, strain, disloca-
tion density and unit cell volume were calculated. Compressibility was performed in a
hardened steel die at pressures between 100 to 500 MPa to determine Al with 5 wt.% TiO 2
and 2 & 4 wt.% of Gr powder mixtures. For understanding of compaction behavior of alu-
minum based hybrid composites reinforced with TiO 2 and Gr particles under various
applied pressure conditions, experimental research has been made using several powder
compaction equations. Microstructure analysis for Al + 5% TiO 2 + 6% Gr composite has
been reported.
Key words: ball milling, synthesis, composite powders, ball milling.
Aluminum matrix composites are used for various applications in aerospace, auto-
mobile, military and electronic industry due to their low density, high toughness, good
mechanical properties and high corrosion resistance [1]. Many varieties of reinforce-
ments are used to produce the aluminium matrix composites. Instead of all, the titani-
um-di-oxide (TiO 2) also found as a good one, since it has high hardness, high modulus,
and wear resistance [2]. Adding of single reinforcement to the matrix material im-
proves the strength and hardness of the material, but it leads to the machining problem
[3]. Recently aluminum alloy–graphite particulate composite is being used in various
applications because of its low friction and wear, improved machinability, low thermal
expansion and high damping density [4]. In this work both the hard TiO 2 and soft gra-
phite powders are used as reinforcements to produce the aluminium hybrid composites
and it is expected to be used for various application. The mechanical alloying process
is used to produce the advanced composite materials [5]. Mechanical alloying is a wi-
dely used technique in synthesizing nanocrystalline materials and also it has been used
to prevent the reinforcement clusters or agglomerates on the matrix, especially in the
case of small size reinforcement particles that produce uniform dispersion in the mat-
rix. The homogeneous dispersion of fine reinforced particles in a fine grained matrix is
beneficial to the mechanical properties of metal matrix composites [2]. A number of re-
search works have been performed on processing of aluminum matrix composites via
mechanical milling. Meanwhile, mechanical milling affects the morphology and hard-
ness of powder particles, thus it influences the compressibility of milled powders [6].

Corresponding author: M. RAVICHANDRAN, e-mail: smravichandran@hotmail.com
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