Role of Mg2Si particles on mechanical, wear, and corrosion behaviors of friction stir welding of AA6061-T6 and Al-Mg2Si composite

This paper investigates the effect of different tool pin morphologies on the inter-mixing capability, microstructure, mechanical properties, corrosion, fracture, and wear behaviors of the dissimilar friction stir welded AA6061-T6 alloy--Al 20wt% Mg2Si composite. Grooved shoulder tools with varying pin profiles such as tapered cylindrical, threaded tapered cylindrical, and triangular tapered pins were used for joining the base materials. The parameter combination of 80 mm/min travel speed and 1000 r/min rotation speed (at which no visible flow-induced defect was obtained) was used for this study. Among the pin profiles, the triangular tapered pin produced significantly improved intermingling/inter-material flow, fragmentation, and dispersion of the primary Mg2Si particles in the AA6061-T6/Al-Mg2Si joint. The triangular tapered tool reduced the average grain sizes of the AA6061 alloy and the Mg2Si particles from 18.4 to 4.6 µm and from 115 to 7.5 µm, respectively. Intermetallic phases of Mg2Si, AlFe, Al3.21Si0.47, and Al0.7Fe3Si0.3 are formed in the weld nugget of all the AA6061/Al-Mg2Si joints. The tensile strengths of the joints fabricated with tapered cylindrical, threaded tapered cylindrical, and triangular tapered tools are 108, 139, and 141 MPa, respectively. Abrasive wear is promoted in the joints fabricated with triangular tapered tool due to the homogeneous dispersion and fragmentation of the inherent hard Mg2Si particles. The corrosion attack is dependent on the fragmentation level of the Mg2Si phase. Triangular tapered pin tool is recommended for dissimilar Al/composite welding due to favorable tool-induced material flow, dispersion, and fragmentation of reinforcement.

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Interaction between Sodium Molybdate and FSWed Wled of 5083 Effected by Time

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.699.645 ◽

2013 ◽

Vol 699 ◽

pp. 645-649

Author(s):

Chang Bin Shen

Keyword(s):

Inhibition Efficiency ◽

Electrochemical Impedance ◽

Electrochemical Corrosion ◽

Sodium Molybdate ◽

Impedance Spectra ◽

Electrochemical Impedance Spectra ◽

Friction Stir ◽

Base Materials ◽

Corrosion Behaviors ◽

5083 Aluminum Alloy

Similar welds composed of 5083 were produced by friction stir welding. In the solution of 0.2 M NaHSO3 and 0.6 M NaCl, with the addition of a given concentration sodium molybdate as the inhibitor, the electrochemical corrosion behaviors of the friction stir welds (FSW) and 5083 were comparatively investigated by potentiodynamic polarization curve tests and electrochemical impedance spectra (EIS) at the ambient temperature for different test periods. The results indicated that : with the extension of period, the inhibition efficiencies (IE) for both the weld and 5083 base materials enhanced, at the same period, the inhibition efficiency (IE) for the weld was beyond that for 5083 base materials, sodium molybdate may be thought of as an effective inhibitor for 5083 aluminum alloy, the interaction between inhibitor and weld is stronger than that between inhibitor and base materials.

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Recent development in friction stir processing of aluminum alloys: Microstructure evolution, mechanical properties, wear and corrosion behaviors

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

10.1177/09544089211058007 ◽

2021 ◽

pp. 095440892110580

Author(s):

Behrouz Bagheri ◽

Amin Abdollahzadeh ◽

Farzaneh Sharifi ◽

Mahmoud Abbasi ◽

Ahmad Ostovari Moghaddam

Keyword(s):

Mechanical Properties ◽

Friction Stir Processing ◽

Mechanical Vibration ◽

Friction Stir ◽

Microstructure Modification ◽

Surface Composites ◽

Wear And Corrosion ◽

Corrosion Behaviors ◽

Strengthening Particles ◽

Aluminum Alloy Surface

In this paper, the effect of mechanical vibration with reinforcement particles namely Silicon Carbide (SiC) on microstructure, mechanical properties, wear, and corrosion behaviors of aluminum alloy surface composites fabricated via friction stir processing (FSP) was investigated. The method was entitled friction stir vibration process (FSVP). The results revealed that recrystallized fine grains formed in all processing samples as a result of dynamic recovery and recrystallization, while samples processed in friction stir vibration processing resulted in better grain refinement in the stir zone than in conventional friction stir processing. Compared to conventional friction stir processing, in friction stir vibration processing, the hardness and tensile strength increased due to microstructure modification and better reinforcing distribution. From corrosion analysis, the corrosion resistance of the friction stir vibration processed samples showed a significant increase compared to the friction stir processed specimens. The wear results indicated that the wear resistance of friction stir vibration processed specimens is higher than friction stir processed specimens due to the development of smaller grains and a more homogenous distribution of the strengthening particles as the vibration is applied.

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The Influence of Cu/Ti Overlapping Region Microstructures on the Mechanical Tensile Properties of the Joint via Friction Stir Lap Welding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1142.260 ◽

2017 ◽

Vol 1142 ◽

pp. 260-264 ◽

Cited By ~ 2

Author(s):

Bo Li ◽

Yi Fu Shen ◽

Lei Yao

Keyword(s):

Tensile Properties ◽

Travel Speed ◽

Lap Joints ◽

Friction Stir Lap Welding ◽

Friction Stir ◽

Lap Welding ◽

Mechanical Tensile ◽

Tool Pin ◽

Solid State Joining ◽

Locking Effect

The investigation on friction stir lap welding (FSLW) of dissimilar Cu and Ti is reported in this research, aiming to achieve a reliable solid-state joining and effectively control the intermetellic (IMC) formation at the lapping Cu/Ti dissimilar welded interfaces. Following the previous process optimization of the FSLW tool rotation speed and downward plunge value of the tool pin into the lower Ti sheet, the tool travel speed was further tailored for a defect-free joint. No significant Ti-Cu IMC was founded in the generated joints. After the analyses of tensile properties of the FSLW joints, the so-called mechanical locking effect of the Cu/Ti alternate band structure was further elucidated. The composite-like structure played a so-called mechanical locking effect on the Cu/Ti lap joints. The fracture resistant strength of the joint reached 95% of that of the used parent copper.

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Numerical Study of the Tool Rake Angle Effect on the Material Flow in Friction Stir Welding Process

Volume 3: Design and Manufacturing ◽

10.1115/imece2007-41962 ◽

2007 ◽

Cited By ~ 1

Author(s):

Hosein Atharifar ◽

Radovan Kovacevic

Keyword(s):

Friction Stir Welding ◽

Material Flow ◽

Numerical Study ◽

Welding Process ◽

Rake Angle ◽

Heat Transfer Analysis ◽

Tool Geometry ◽

Friction Stir ◽

Tool Pin ◽

Welding Processes

Minimizing consumed energy in friction stir welding (FSW) is one of the prominent considerations in the process development. Modifications of the FSW tool geometry might be categorized as the initial attempt to achieve a minimum FSW effort. Advanced tool pin and shoulder features as well as a low-conductive backing plate, high-conductive FSW tools equipped with cooling fins, and single or multi-step welding processes are all carried out to achieve a flawless weld with reduced welding effort. The outcomes of these attempts are considerable, primarily when the tool pin traditional designs are replaced with threaded, Trifiute or Trivex geometries. Nevertheless, the problem remains as to how an inclined tool affects the material flow characteristics and the loads applied to the tool. It is experimentally proven that a positive rake angle facilitates the traverse motion of the FSW tool; however, few computational evidences were provided. In this study, numerical material flow and heat transfer analysis are carried out for the presumed tool rake angle ranging from −4° to 4°. Afterwards, the effects of the tool rake angle to the dynamic pressure distribution, strain-rates, and velocity profiles are numerically computed. Furthermore, coefficients of drag, lift, and side force and moment applied to the tool from the visco-plastic material region are computed for each of the tool rake angles. Eventually, this paper confirms that the rake angle dramatically affects the magnitude of the loads applied to the FSW tool, and the developed advanced numerical model might be used to find optimum tool rake angle for other aluminum alloys.

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Influence of Nano Reinforcement Volume Percentage on Fabrication of Surface Nanocomposite by FSP

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.1369 ◽

2016 ◽

Vol 879 ◽

pp. 1369-1374

Author(s):

P. Naresh ◽

Adepu Kumar ◽

M. Krishna Kishore

Keyword(s):

Material Flow ◽

Volume Fraction ◽

Traverse Speed ◽

Stir Zone ◽

Tool Rotational Speed ◽

Volume Percentage ◽

Phase Volume Fraction ◽

Friction Stir ◽

Surface Composite

This work deals with the effect of volume percentage of nanoreinforcement to fabricate nanosurface composite by Friction Stir Processing (FSP) and also studied the role of tool rotational speed and traverse speed to get the defect free condition to fabricate successful surface composite. The material flow pattern, dispersion of the reinforcement particles in the stir zone was examined. From the phase/volume fraction analysis, it was observed that the nanoAl2O3 particles were well dispersed in the stir zone. The results indicate that the better microstructural, mechanical properties were obtained at 1150rpm /15mm/min condition. A significant improvement in microhardness was exhibited by surface nanocomposite as compared to the as - received aluminum.

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The Effect of Tool Pin Size and Taper Angle on the Thermal Process and Plastic Material Flow in Friction Stir Welding

10.21203/rs.3.rs-335152/v1 ◽

2021 ◽

Author(s):

Jie Chen ◽

Lei Shi ◽

Chuansong Wu ◽

Yuanning Jiang

Keyword(s):

Friction Stir Welding ◽

Shear Layer ◽

Layer Thickness ◽

Material Flow ◽

Horizontal Plane ◽

Thermal Process ◽

Plastic Material ◽

Taper Angle ◽

Friction Stir ◽

Tool Pin

Abstract Friction stir welding (FSW) tool pin, as a critical component of FSW tool, plays an important role in determining the final joint properties by affecting the heat generation, plastic material flow, welding loads and so on. However, the influence of tool pin on heat and mass transfer in FSW are not elucidated. In the present study, a validated model was adopted to quantitatively analyze the effects of pin size and taper angle on the thermal process and plastic material flow in FSW. It reveals that the torque and transverse force imposed on the pin are increased with the increase of the pin diameters (including its root diameter, its tip diameter and its size in condition of constant taper angle), while the total tool torque various a little for the tool pin diameter considered in this study. When the pin diameters increase, the viscosity of the materials near the pin is decreased, while the temperature as well as the flow velocity is increased. More plastic material near the tool could rotate around the tool with an increase of the pin diameter. The TMAZ boundary is enlarged with larger pin diameters in FSW. Particularly, the shear layer thickness of the same horizontal plane in the range of 1 mm < z < 5 mm is significantly enlarged with an increase of pin root diameters. However, the shear layer thickness of the same horizontal plane in the region of z < 5 mm is increased when using a larger pin tip diameter. In addition, maximum width of TMAZ boundary at the top surface of workpiece was not affected by pin diameters. The model is validated by experimental results. It lays solid foundation for optimizing the tool pin size and taper angle in FSW.

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Numerical Studies on Temperature and Material Flow During Friction Stir Welding using Different Tool Pin Profiles

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences ◽

10.37934/arfmts.83.1.91104 ◽

2021 ◽

Vol 83 (1) ◽

pp. 91-104

Author(s):

M. D. Bindu ◽

P. S. Tide ◽

A. B. Bhasi

Keyword(s):

Friction Stir Welding ◽

Temperature Distribution ◽

Material Flow ◽

Three Dimensional ◽

Friction Stir ◽

Specific Strength ◽

Numerical Studies ◽

Computational Fluid Dynamics Cfd ◽

Tool Pin ◽

Metal Hardness

A three dimensional computational fluid dynamics (CFD) model has been developed to study the effect of tool pin profile on the material flow and temperature development in friction stir welding (FSW) of high specific strength AA 7068 alloy. Numerical simulations were carried out using a RNG k-e turbulence model. Three tool pin profiles, viz. cylindrical, conical and straight cylindrical threaded were considered for the simulation. The temperature distribution and material flow pattern obtained from the simulation were compared for different pin profiles. Simulation results predicted Temperature distribution and material maxing was better in straight cylindrical tapered thread pin welds. Weld joints were fabricated using the straight cylindrical threaded pin with the same parametric combinations as in the simulation. Peak temperature measured in the experiment was less than that obtained by simulation. Hardness measurements taken at different weld regions has showed that about 71% of that of the base metal hardness is obtained with the threaded tool pin. The microstructure study revealed a defect free weld joint. Precipitates distributed in the microstructure indicate sufficient heat input to join the material without dissolving precipitates. The developed numerical model is helpful in optimising FSW process parameters.

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Optimal FSW Process Parameters to Improve the Strength of Dissimilar AA6061-T6 to Cu Welds with Zn Interlayer

International Journal of Recent Technology and Engineering - 2 ◽

10.35940/ijrte.d9804.118419 ◽

2019 ◽

Vol 8 (4) ◽

pp. 11688-11695

Keyword(s):

Process Parameters ◽

Empirical Relation ◽

Travel Speed ◽

Strength Properties ◽

Dissimilar Welding ◽

Test Results ◽

Friction Stir ◽

Taguchi Design Of Experiments ◽

Potential Applications ◽

Tool Pin

Dissimilar welding of Al-Cu has many potential applications in electric power, electronic and piping industries due to high corrosion resistance, heat and conducting properties. Weld joints through friction stir welding (FSW) process are free from melting- and solidification-related defects. Compared to the recently used Box–Behnken design of response surface methodology, a simple and reliable modified Taguchi design of experiments is utilized for the dissimilar welding of AA6061-T6 to Cu with Zn interlayer to obtain the optimal FSW process parameters and the expected range of strength properties. Empirical relation for the tensile strength is developed in terms of FSW process parameters (viz., tool rotation speed, tool travel speed and tool pin offset) and validated through test results. Most of the test data are within the expected range.

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