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Synthesis and characterization of titanium carbide particulate reinforced AA6082 aluminium alloy composites via friction stir processing

Thangarasu A., Murugan N., Dinaharan I., Vijay S. J.

Archives of Civil and Mechanical Engineering

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2015

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Vol. 15, no. 2

324--334

EN

Friction stir processing (FSP) has evolved as a novel solid state technique to fabricate aluminium matrix composites (AMCs) in the recent years. FSP technique was applied to synthesis AA6082/TiC AMCs in order to analyze the effect of TiC particles, its volume fraction on the microstructure, mechanical and the sliding wear behaviour. A single pass FSP was carried out using a tool with 1200 rpm rotational speed, whose travel speed of 60 mm/min and an axial force of 10 kN to produce the composite. AMCs with five different volume fractions (0, 6, 12, 18 and 24 vol.%) were synthesized. The microstructure of the AA6082/TiC AMCs was studied using optical and scanning electron microscopy. The microhardness and ultimate tensile strength (UTS) were measured and the sliding wear behaviour was evaluated using a pin-on-disc apparatus. Thus the results revealed that the TiC particles significantly influenced the area of the composite, dispersion, grain size of matrix, microhardness, UTS and sliding wear behaviour of the AA6082/TiC AMCs. With this the effect of TiC particles on fracture surface and worn surface is also reported in this paper.

2

Fabrication and Characterization of CU/B4 C Surface Dispersion Strengthened Composite using Friction Stir Processing

Sathiskumar R., Murugan N., Dinaharan I., Vijay S. J.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 1

83--87

EN

Friction stir processing has evolved as a novel method to fabricate surface metal matrix composites. The feasibility to make B4 C particulate reinforced copper surface matrix composite is detailed in this paper. The B4 C powders were compacted into a groove of width 0.5 mm and depth 5 mm on a 9.5 mm thick copper plate. A tool made of high carbon high chromium steel; oil hardened to 63 HRC, having cylindrical profile was used in this study. A single pass friction stir processing was carried out using a tool rotational speed of 1500 rpm, processing speed of 40 mm/min and axial force of 10 kN. A defect free interface between the matrix and the composite layer was achieved. The optical and scanning electron micrographs revealed a homogeneous distribution of B4 C particles which were well bonded with the matrix. The hardness of the friction stir processed zone increased by 26% higher to that of the matrix material.

PL

Zgrzewanie tarciowe ewoluowało jako nowa metoda wytwarzania kompozytów powierzchniowych z osnową metaliczną. W pracy szczegółowo opisano możliwość wytworzenia kompozytu na powierzchni miedzi zbrojonego cząstkami B4 C. Proszki B4 C sprasowano w rowku o szerokości 0,5 mm i głębokści 5 mm wykonanym na blasze miedzianej o grubości 9,5 mm. Do wytworzenia kompozytu użyto narzędzia o profilu cylindrycznym, z wysokowęglowej stali o wysokiej zawartości chromu, hartowanego w oleju do 63 HRC. W jednym przebiegu obróbki zgrzewanie przeprowadzono przy prędkości obrotowej narzędzia 1500 obr/min. szybkości przesuwu 40 mm/min i osiowej siły 10 kN. Osiągnięto cel w postaci pozbawionego wad połączenia pomiędzy matrycą i warstwą kompozytu. Mikrofotografie optyczne i ze skaningowej mikroskopii elektronowej wykazały jednorodną dystrybucję cząstek B-C, które były dobrze połączone z matrycą. Twardość strefy zgrzewnej tarciowo wzrosła o 26% w stosunku do materiału matrycy.

3

Effect of TiB2 content and temperature on sliding wear behavior of AA7075/TiB2 in situ aluminum cast composite

Michael Rajan H. B., Ramabalan S., Dinaharan I., Vijay S. J.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 1

72--79

EN

Aluminum alloy AA7075 reinforced TiB2 particulate composites were prepared by the in situ reaction of K2TiF6 and KBF4 to molten aluminum. The prepared aluminum matrix composites (AMCs) were characterized using X-ray diffraction and scanning electron microscopy (SEM). The sliding wear behavior of the AMCs was evaluated using a pin-on-disc wear apparatus. The effect of TiB2 particulate content (0, 3, 6 and 9 wt%) and temperature (30, 60, 90, 120, 150, 180, 210 and 240 °C) on wear rate and worn surface of the AMCs were studied. The results indicated that TiB2 particles were effective to enhance the wear resistance of the AMCs at all test temperatures studied in this work. The wear rate of the AMCs increased when the applied temperature was increased. The in situ formed TiB2 particles pushed the transition wear temperature by another 30 °C. The wear mode was observed to be abrasive at room temperature and metal flow at high temperature.

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Effect of material location and tool rotational speed on microstructure and tensile strength of dissimilar friction stir welded aluminum alloys

Dinaharan I., Kalaiselvan K., Vijay S. J., Raja P.

Archives of Civil and Mechanical Engineering

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2012

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Vol. 12, no. 4

446--454

EN

The dissimilar welding of cast and wrought aluminum alloys has high potential to expand the usage of economical castings. Friction stir welding (FSW) is an appropriate technique to join dissimilar aluminum alloys. The present work investigates the effect of material location and tool rotational speed on microstructure and tensile strength of dissimilar friction stir welded cast and wrought aluminum alloy AA6061. Eight joints were made using four tool rotational speeds by changing the location of each aluminum alloy in advancing and retreading sides. The results indicated that the material location prior to welding and tool rotational speed significantly influenced the material flow behavior. The material placed in the advancing side occupied the major portion of the weld zone when tool rotational speed was increased. The microstructure of the dissimilar joints exhibited the presence of four zones namely base metal, heat affected zone, thermomechanically affected zone and weld zone. The weld zone revealed two kinds of regions namely unmixed region and mechanically mixed region. The dissimilar joint showed maximum tensile strength when cast aluminum alloy was placed in the advancing side at all tool rotational speeds.