Microstructures and mechanical properties of Al/Al2O3 surface nano-composite layer produced by friction stir processing

Friction stir processing is a novel material fabrication technique. This study was undertaken in order to investigate a suitable set of friction stir processing parameters to form AL7075T651/TiN nano composite. A number of samples were produced by varying the process parameters, namely, tool-pin geometry, number of passes and the direction of tool rotation. The pin geometries employed include triangular, square and threaded taper; the passes were varied over two levels (i.e. 2 and 4) and the tool rotation was changed as clockwise and counter clockwise between the successive passes. The effect of these variations on the composite was quantified through several microstructural and mechanical tests. The increase in the number of passes was observed to improve various characteristics of the composite (i.e. distribution of TiN particles, grain refinement and mechanical properties). The effect of tool geometry, however, was associated with the choice of the number of passes. The change in the direction of tool rotation between the consecutive passes was witnessed to improve the distribution of TiN particles. From the X-ray diffraction analysis of the samples, the formation of several new phases was detected. These were found to have effect on the mechanical properties of the composite. A good trade-off among various properties of the composite (i.e. hardness, tensile strength and ductility) was realized when the friction stir processing was performed using square tool and employing four passes with simultaneously changing the direction of tool rotation between the successive passes. This study is the first report on the fabrication of AL7075T651/TiN nano composite through friction stir processing route.

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FABRICATION OF TI/SIC SURFACE NANO-COMPOSITE LAYER BY FRICTION STIR PROCESSING

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194512002243 ◽

2012 ◽

Vol 05 ◽

pp. 367-374 ◽

Cited By ~ 2

Author(s):

ALI SHAMSIPUR ◽

SEYED FARSHID KASHANI-BOZORG ◽

ABBAS ZAREIE-HANZAKI

Keyword(s):

Friction Stir Processing ◽

Composite Layer ◽

Pure Titanium ◽

Titanium Substrate ◽

Commercially Pure Titanium ◽

Nano Composite ◽

Composite Surface ◽

Friction Stir ◽

Commercially Pure ◽

Sic Particles

In the present investigation, novel Ti / SiC surface nano-composite layer was successfully fabricated by dispersing nano-sized SiC particles into commercially pure titanium plates employing friction stir processing technique. The process parameters such as tool rotation and advancing speeds were adjusted to produce defect-free surface composite layer, however, uniform distribution of the nano-size SiC particles in a matrix of titanium was achieved after the second pass. The micro hardness value of the Ti / SiC nano-composite surface layer was found to be ~534 HV; this is 3.3 times higher than that of the commercially pure titanium substrate. No reaction was detected between SiC powders and the titanium matrix after friction stir processing.

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Friction Stir Processing (FSP) of Cast Metals: Microstructure – Property Relationships in NiAl Bronze and AA5083

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.35 ◽

2010 ◽

Vol 638-642 ◽

pp. 35-40

Author(s):

Terry R. McNelley ◽

Srinivasan Swaminathan ◽

E. Sarath Menon ◽

J.Q. Su

Keyword(s):

Mechanical Properties ◽

Ambient Temperature ◽

Friction Stir Processing ◽

Elevated Temperatures ◽

Stir Zone ◽

Friction Stir ◽

Grain Structures ◽

Microstructures And Mechanical Properties ◽

Step Over ◽

Equiaxed Grain

Parameters for multi-pass FSP include the pattern of tool traverse and step-over distance between successive passes. Multi-pass FSP was conducted on as-cast NiAl bronze and as-cast AA5083 in order to modify stir zone (SZ) microstructures and mechanical properties. Highly refined and homogeneous SZ microstructures may be produced by FSP. Refined and equiaxed grain structures reflect recrystallization during FSP; mechanisms leading to homogenization by redistribution of microstructure constituents remain to be determined. Refined microstructures exhibit enhanced ambient-temperature properties and superplasticity at elevated temperatures.

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EFFECT OF ADDING BORON CARBIDE (B4C) TO POLYMER FOR PRODUCING SURFACE COMPOSITE BY FRICTION STIR PROCESSING

THE IRAQI JOURNAL FOR MECHANICAL AND MATERIALS ENGINEERING ◽

10.32852/iqjfmme.v18i3.178 ◽

2018 ◽

Vol 18 (3) ◽

pp. 436-445

Author(s):

Bashaer A Habeeb ◽

Ahmed O Al-Roubaiy

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Friction Stir Processing ◽

Composite Layer ◽

Wear Test ◽

Homogeneous Distribution ◽

Cylindrical Shape ◽

Test Results ◽

Processing Technologies ◽

Friction Stir

Friction stir processing (FSP) is a new solid state technique, it is employed for theimprovement of the mechanical properties of a material and the production of surface layercomposites instead of conventional processing technologies. This research aims to study theability of applying Friction Stir Processing (FSP) to modify the surface of high densitypolyethylene (HDPE) reinforcing by B4C with a particle size of 0.4?m, Groove in themiddle of HDPE surface made to fill by B4C. Varity in the groove depth (0.6, 1.2 and1.8)mm used according to B4C ratio on HDPE substrate particles. Friction stir process wascarried out, using tool with cylindrical shape of pin and shoe tool to produce surface layercomposite. The effect of processing parameters including rotational and transverse speeds onthe mechanical properties of composite layer was studied. Wear test results show apronounced improvement in wear resistance of HDPE surface through reinforcementadditions of B4C at a ratio (5%, 10% and 15% ), where wear rate improved by (60%, 71%and 63%) respectively, as compared with as received HDPE, the surface compositeHDPE/B4C have good wear resistance. Hardness test results indicate that the hardness ofcomposite layer reinforced with (5%,10% and 15%) particles improved by( 26%, 35% and28% )respectively as compared with received HDPE. OM revealed that high tool rotationalspeed resulted in homogeneous distribution of B4C particles and vice versa.

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Effect of friction stir processing on microstructures and mechanical properties of TIG cladding layer on AA7075

Materials Research Express ◽

10.1088/2053-1591/ac3e95 ◽

2021 ◽

Author(s):

Chao Shi ◽

Chao Liu ◽

Kaizhen Zhu

Keyword(s):

Mechanical Properties ◽

Tensile Properties ◽

Friction Stir Processing ◽

Rotational Speed ◽

Traverse Speed ◽

Stir Zone ◽

Elemental Distribution ◽

Friction Stir ◽

Cladding Layer ◽

Microstructures And Mechanical Properties

Abstract AA7075 is a precipitation strengthened Al-Zn-Mg-Cu alloy which has been widely used. As a common way to repair AA7075 components, tungsten inert gas (TIG) cladding generates coarse grains and defects. In addition, the use of other types of filler wires could lead to insufficient rigidity and strength of the cladding layer. In the present work, friction stir processing (FSP) has been applied to the TIG cladding layer on AA7075 to study the effect of process parameters on microstructures and mechanical properties. The macro/micro structural characteristics, elemental distribution, microhardness distribution and tensile properties have been investigated. The macroscopic defects in TIG cladding layer are eliminated and the size of grains is decreases to around 6 μm by FSP. FSP reduces the compositional difference between the stir zone and the base material. Higher rotational speed promotes the grain refinement while the lower traverse speed benefits the microstructural uniformity. FSP on the TIG weld bead brings improvement in tensile properties and hardness. All the fractures for TIG+FSP samples occur at thermo-mechanically affected zone of the advancing side. The tensile strength of the stir zone increases from 424.2 to 442.8 MPa with the increase in rotational speed and traverse speed.

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