Microstructure and corrosion properties of 5A06 aluminum matrix surface composite fabricated by friction stir processing

Friction stir processing (FSP) is an emerging method for improving surface properties of materials by composite fabrication. This study aims at optimizing the major FSP parameters and analysis of their real-time influence on the mechanical performance of a surface composite fabricated with Magnesium (Mg) matrix and Titanium Carbide (TiC) as reinforcement. Effects of different process parameters, tool rotational speed, plunge depth, the linear speed of the tool, cooling condition, and number of FSP passes have been examined. Using L27 array, a total of 27 combinations of these process parameters were analyzed by taking microhardness as an output response to find influential parameters by Taguchi's technique. Maximum micro-hardness was achieved when tool rpm of 600, cooling temperature of -10o C, tool feed of 15 mm/min, plunge depth of 0.35 mm, and 3 passes of FSP tool were chosen with the help of Taguchi's method. Analysis of variance indicated that cooling temperature, the tool feed, and the number of passes of the FSP tool were the most significant parameters.

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FABRICATION OF SURFACE COMPOSITE BY FRICTION STIR PROCESSING USING A NOVEL DIRECT PARTICLE INJECTION TOOL

Surface Review and Letters ◽

10.1142/s0218625x18501822 ◽

2019 ◽

Vol 26 (04) ◽

pp. 1850182

Author(s):

P. MUTHUKUMAR ◽

S. JEROME ◽

R. JOHN FELIX KUMAR ◽

S. PRAKASH

Keyword(s):

Friction Stir Processing ◽

Composite Layer ◽

Aluminum Matrix ◽

Homogeneous Distribution ◽

Particle Injection ◽

Friction Stir ◽

Surface Composite ◽

Surface Composite Layer ◽

The Matrix ◽

The Impact

In this work, aluminum/titanium carbide (Al/TiC) surface composite has been fabricated by friction stir processing using a novel modular Direct Particle Injection Tool (DPI–FSP). The tool has a unique feature wherein the TiC particles have been transferred from the tool itself by spring adjusted plunger movement into the matrix. The microstructural observations from optical and scanning electron microscope (SEM)-EDS results revealed the homogeneous distribution of particles in the stirred zone (SZ) and the thickness of the formed surface composite layer (SCL) is approximately 0.34[Formula: see text]mm. X-ray diffraction results confirmed that the particles are reinforced in the aluminum matrix, and no intermetallics have been formed in the composite. The microhardness of composite was increased from 68 to 135[Formula: see text]Hv, and the impact test results showed that the toughness was almost comparable to that of the base metal.

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MICROSTRUCTURAL PROPERTIES AND PHASE CONSTITUENTS OF 5A06 ALUMINIUM MATRIX SURFACE COMPOSITE FABRICATED BY FRICTION STIR PROCESSING

Surface Review and Letters ◽

10.1142/s0218625x1101462x ◽

2011 ◽

Vol 18 (05) ◽

pp. 183-188

Author(s):

LIU PENG ◽

QING-YU SHI ◽

YUAN-BIN ZHANG ◽

SHU-BO XU

Keyword(s):

Base Metal ◽

Friction Stir Processing ◽

Aluminium Matrix ◽

Air Cooling ◽

Friction Stir ◽

Surface Composite ◽

Ultrafine Grained ◽

Matrix Surface ◽

Average Grain Size ◽

Amorphous Structures

A novel aluminium matrix surface composite added Al -based amorphous, whose layer depth was 5 mm, was fabricated by friction stir processing (FSP), at an air cooling. The surface composite region shows the obvious sandwich structure. It is considered to be a combination between the base metal and the amorphous strip via the FSP. The average hardness of the surface composite is about HV97, higher than the base metal is about HV80. The maximum tensile strength of the processed aluminium plate with the surface composite is 410 MPa. XRD results indicate that the constituent phases of the surface composite mainly include α- Al , Mg2Al3 , MnAl6 and La3Al11 Moreover, no obvious amorphous diffraction peaks are observed in the XRD results. However, a large number of ultrafine grained structures can be observed in the surface composite. The average grain size of them is ~90–400 nm constitutes the surface composite. These ultrafine grained structures are composed of the α- Al and α- Al amorphous structures.

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Fabrication of Hybrid Surface Composites AA6061/(B4C + MoS2) via Friction Stir Processing

Journal of Tribology ◽

10.1115/1.4043067 ◽

2019 ◽

Vol 141 (5) ◽

Cited By ~ 14

Author(s):

Daulat Kumar Sharma ◽

Vivek Patel ◽

Vishvesh Badheka ◽

Krunal Mehta ◽

Gautam Upadhyay

Keyword(s):

Wear Resistance ◽

Aluminum Alloys ◽

Friction Stir Processing ◽

Solid Lubricant ◽

Hybrid Composites ◽

Aluminum Matrix ◽

Friction Stir ◽

Surface Composite ◽

Surface Composites ◽

Structural Applications

Poor tribological properties restrict structural applications of aluminum alloys and surface composites of aluminum alloys have gained more attention in material processing. The addition of solid lubricant reinforcement particles along with abrasive ceramics contributes to the enhancement of tribological performance of surface composites. In the present study, the solid-state technique, friction stir processing (FSP) was used to develop mono (B4C) and hybrid (B4C + MoS2) surface composites in the AA6061-T651 aluminum alloy. The hybrid surface composites were produced by varying an amount of MoS2. Multipass FSP with different direction strategies was adopted for achieving uniform distribution of reinforcement powders in the aluminum matrix. Microstructure analysis showed a uniform dispersal of reinforcement particles without any clustering or agglomeration in the processing zone. Microhardness and wear performance of mono and hybrid composites improved in comparison with the base metal. The mono surface composite exhibited the highest hardness while the hybrid surface composite (75%B4C + 25%MoS2) achieved the highest wear resistance. This was attributed to the solid lubricant nature of MoS2. Furthermore, dissolution of the strengthening precipitate condition during multipass FSP without reinforcement particles resulted in the reduction of hardness and wear resistance.

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Machinability of AA7075-T6/carbon nanotube surface composite fabricated by friction stir processing

Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering ◽

10.1177/0954408918809618 ◽

2018 ◽

Vol 233 (4) ◽

pp. 839-848 ◽

Cited By ~ 2

Author(s):

Ramin Mehdizad Tekiyeh ◽

Mohsen Najafi ◽

Saeid Shahraki

Keyword(s):

Carbon Nanotube ◽

Friction Stir Processing ◽

Aluminum Matrix ◽

Wear Test ◽

Travel Speed ◽

Raw Material ◽

Subsequent Formation ◽

Friction Stir ◽

Surface Composite ◽

Uniform Dispersion

Chip adhesion on rake face of cutting tool and subsequent formation of built-up-edge are critical problems in machining of aluminum alloys. In the current work, carbon nanotube as a solid lubricant has been integrated with aluminum 7075-T6 alloy through friction stir processing and the machinability of fabricated surface composite has been evaluated. Here, firstly, a series of friction stir processing experiment has been carried out to find optimum pass number regarding uniform dispersion of carbon nanotube in aluminum matrix. Then, a total number of 27 drilling experiments under different values of spindle speed and travel speed have been carried out on raw material, friction stir processed material without addition of carbon nanotube, and friction stir processed with addition of carbon nanotube. The obtained results showed that addition of carbon nanotube as reinforcement causes reduction of machining thrust force and surface roughness due to excellent lubrication property. Tribological observations through scanning electron microscopy and wear test revealed that the main mechanism for enhancing the machinability is reduction of friction coefficient as a result of carbon nanotube addition.

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