Influence Of Tool Pin Profile Research Articles

Influence of Tool Pin Profiles on Aluminium Alloy A356 and Ceramic-Based Nanocomposites for Light Weight Structures by Friction Stir Processing

In this research, the main aim is to focus the enhancement of aluminium-based metal matrix composites for improving the attributes of light weight metals, aerospace structures and other tailor blank material properties. By this way, the friction stir processing (FSP) was the suited alternate technique to enhancing the mechanical attributes and superior microstructural amendment in the processed MMCs. Therefore, this study investigates the dispersion of ceramic-based strengthening particles of chromium oxide (Cr2O3) in the aluminium base matrix of A356 alloy. During the processing, the different tool pin sizes having the conical threaded tool pin profiles. Similarly, the tool spinning speed and tool travel speed also varied while in FSP. Before the processing, the A356 alloy was prepared by the grooved surfaces for packing the chromium oxide particles to compose the aluminium metal matrix composites. The tensile strength and hardness was employed to carry out from the friction stir processed A356 alloy with influencing of Cr2O3. The maximum occurred tensile processing parameters are 1500 rpm of spinning speed, 6 mm of tool pin sizes and 90 mm/min of tool travel speed. Similarly, the maximum obtained hardness processing parameter are 2000 rpm of spinning speed, 5 mm of tool pin sizes and 90 mm/min of tool travel speed. A scanning electron microscope was utilized to investigate the dispersed Cr2O3 in the A356 alloy for confirming the refinement grains in the nugget zones of FSPed A356 alloy. The increased grain boundary by the influence of different tool pin sizes was the major reason to produces the better mechanical properties in the processed A356/Cr2O3.

Influence of Tool Pin Profile and Welding Parameters on Microstructure and Mechanical Properties of Dissimilar Friction Stir Welded AA2024 to AA7075 Alloys

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Influence of tool pin profile on the mechanical strength and surface roughness of AA6061-T6 overlap joint friction stir welding

This study presents the tensile strength and surface roughness resulting from friction stir welding (FSW) on the lap joint method using AA 6061 –T6. FSW is conducted by comparing three different tool pin shapes: hexagon, thread, and square. Overlap welding using the FSW method is challenging if machine parameters, such as spindle speed and feed rate, are incompatible. The experiment was conducted using a conventional milling machine with a spindle speed of 1400 -1750 rpm and a feed rate of 20 – 30 mm/min. The results show that a spindle speed of 1750 rpm and a feed rate of 30 mm/min using a square tool pin results in 83.5088 MPa ultimate tensile strength and 0.85 µm surface roughness (Ra), which is much better than hexagon and thread type tool pins. In addition, the overall results on all three tool pin shapes show that higher processing parameters increase tensile strength and surface roughness. This study revealed the effect of parameters on AA6061 –T6 and the resulting implications of mechanical strength and surface roughness.

Influence of tool pin profiles on waviness and natural frequency during friction stir welding of Al-Li alloys plates

The third generation of Al-Li 2050-T84 alloy was primarily used in aerospace industries due to its exceptional potential for weight saving, high strength, and increased fatigue crack growth resistance. In the present research, three different types of tool pin profiles, namely, hybrid, taper threaded, and triangular, were used to join 2050-T84 Al-Li alloy by using Friction Stir Welding (FSW) at a constant rotational speed of 23.33 rotation/second with a traverse speed of 0.003 meters per second and tilt angle of 2°. The research explored the effect of different tools on weld bead structure, waviness and natural frequency of welded plates. The experimental results show that the hybrid tool pin side generates 10.9% higher heat than the threaded taper tool and 25.8% higher than the triangular tool. Moreover, the hybrid tool produces 50.1% lower waviness of welded specimens than the threaded taper tool and 55.7% lower than the triangular tool at the nugget zone (NZ). The research established that a hybrid tool pin profile is advantageous as it generates a higher frequency and lower acceleration under the applied load in friction stir welded specimens.

Influence of tool pin profile on material flow, mechanical properties and corrosion behavior of friction stir welded dissimilar Al5083-6061

In the current investigation, dissimilar aluminum alloys (6 mm thick Al5083 and Al6061) joints were friction stir welded by three different kinds of tool geometries with varied pin features. The results indicated that the formation of the onion ring was confined to a small part of the stir region in the case of triangular pin profile (TP) and square pin profile (SP), whereas the whole stir zone was covered by onion ring or banded structure in case of taper threaded pin profile (TTP). TP and SP show better pulsating action and result in better shearing of the material, causing the material to mix in sideward directions from the advancing side to the retreating side. But, the essential upward and downward material flow to obtain uniform mixing of both base materials were observed in TTP. It contributed to better material flow, and the tool achieved better mechanical and corrosion properties. The hardness values of the joints welded with TP and SP showed uneven distribution in the stir zone, and using TTP could minimize the deviation in hardness values. The role of different tool geometries on material flow, microstructure, corrosion, and mechanical behavior was studied, and the result has been reported and described with detailed analysis.

Experimental investigation and multi-objective optimization of cryogenic Friction-stir-welding of AA2014 and AZ31B alloys using MOORA technique

The cryogenic Friction Stir Welding (CFSW) experimental setup has been designed and fabricated to supply the low-temperature liquid nitrogen supply to perform Friction Stir Welding (FSW) of two dissimilar alloys (Aluminium alloy) AA2014-T6 and (Magnesium alloy) AZ31B. An investigation has been performed to examine the influence of tool pin profile, rotational speed, and welding speed on the welding characteristics: tensile strength, micro-hardness, and percentage of elongation using the Taguchi method. The Multi-Objective Optimization Method by Ratio Analysis (MOORA) technique has been applied to predict the best values of influencing parameters to obtain the optimum welding characteristics. The maximum tensile strength (386.25 MPa), microhardness (120.9HV), and percentage of elongation (20.79 %) were predicted by the stepped square tool pin profile, 1000 rpm tool rotation, and 60 mm/min welding speed. Energy dispersive spectroscopy (EDS) and Scanning Electron Microscope (SEM) analysis were performed to examine the various metallic elements and microstructures. The best optimal set was used to compare the performance of the proposed process with the conventional process. The tensile strength, percentage of elongation, and microhardness of the proposed method are 18.82 %, 19.89 %, and 42.43 % higher than the conventional method.

Influence of tool pin profiles in the strength enhancement of friction stir welded AA5083 and AA5754 alloys

Friction stir welding (FSW) is a well-known technology for joining similar and dissimilar materials. The quality of the weld in FSW is affected by the various process parameters such as tool rotational speed (TRS), tool transverse speed (TTS) and tool pin profiles. This study aims to investigate the effect of three different tool pin profiles on the variation of microstructure and mechanical strength of friction stir welded AA5083 and AA5754 alloys joints. Both of these alloys combinations offer excellent corrosion resistance and formability. As a result, they’re commonly seen in tanks, pressure vessels, shipyards, and trucks. In this work, the FSW methodology focused on varying the TRS of 750, 1000, 1250 and 1500 rpm and TTS as 20, 30, 40 and 50 mm min−1. The surface microstructures of the weldments were analyzed using an optical microscope and scanning electron microscope. Tensile and Microhardness tests were carried out on the weldments to determine the weld strength. Three variety of tool pins, namely straight square, threaded cylinder, and straight cylinder were used for this study. The microstructural and the mechanical properties analysis of the welded samples proved that the straight square tool pin profile is suitable for joining AA5083 and AA5754 alloys. The weldments prepared using a straight square pin profile exhibited good material stream behaviour, uniform spreading of plastic deformation in the weld zone and aided in the reduction of formation of macroscopic defects on the welded zone. Among the process parameters, it was detected that the pin profile displays more impact on tensile strength followed by tool rotation speed and welding speed. According to the findings, the dissimilar weld joint formed at the optimum process parameters had the highest tensile strength of 212 MPa and hardness of 88 HV were: Square Tool Profile, 1250 rpm TRS, and 40 mm min−1 TTS.

Influence of Tool pin Profiles in Friction Stir Welding of Aluminum Alloy and Polycarbonate

In this study, the impact of tool pin profile on the dissimilar joining characteristics of aluminum alloy AA2017 and polycarbonate in friction stir welding (FSW) was examined. The tool pins made of SKD11 tool steel were used in the experiments of the FSW to join AA2017 and polycarbonate plates in a butt configuration at a tool rotation speed of 1320 and 1760 rpm and tool transverse speed of 60 mm/min. The tool shoulder diameter and tool pin height were set to 10 mm and 2 mm. The shapes of tool pin were cylindrical with and without groove, tapered cylindrical with and without groove, bobbin shaped with and without groove, square, triangular, pentagonal, hexagonal, oval, and ellipsoidal. The measurement of axial force was performed using a dynamometer. The changes in workpiece temperature at six locations during the process were measured using K-type thermocouples embedded in the plates. Microstructures of welded joints were examined by an optical microscope. Vickers Microhardness mapping was performed in and around the weld nugget zone, which is formed by the material flow between the two different base materials. From the result, the grooved tool pins generated less heat; while cylindrical, square, and oval type pins are also result in the superior properties of the welds during joining processes. Each tool pin had unique material flow behavior and weld formation, and the weld defects such as tunnel/voids occurred at the joint interface. The oval tool pin gives rise to the highest joint efficiency at a higher tool rotation speed, and the ellipsoidal tool pin generates the highest joint efficiency at a lower tool rotation speed was noticed.

Influence of tool pin profiles on the filler added friction stir spot welded dissimilar aluminium alloy joints

Dissimilar metals are pretty challenging to attain enhanced mechanical properties in the conventional friction stir spot welding (FSSW) process. In this research, a new filler added friction stir spot welding (FAFSSW) process is adopted for welding dissimilar aluminium alloys of AA5052 with AA6061 by using five different tapered tool pins to enhance the mechanical and metallurgical properties of the joints. Magnesium (Mg) powder with 4.5 mg in volume fraction is considered filler material to fabricate the joints. Mechanical properties of the spot weldments like tensile shear strength test, microhardness test, and metallurgical characterizations like microstructure analysis were carried out for FAFSSW joints. The results show that a tool pin profile with 5 mm upper diameter, 2 mm lower diameter and a pin length of 1.2 mm produce a sound joint with 202.85 MPa tensile shear strength and 119.9 HV microhardness. The FAFSSW joint shows 34% higher strength than the normal FSSW joints. The microstructure analysis indicates that the Mg filler mixes well in the weld zone, and a fine grain structure is gained without any defects.

Influence of tool pin profile on mechanical and metallurgical behavior of friction stir welded AA6061-T6 and AA2017-T6 tailored blanks

The heat-treated and artificially aged aluminium alloys of AA6061 and AA2017 are friction stir welded by employing five different tool pin profiles keeping the other process parameters constant. From this investigation, the mechanical properties of welded blanks were evaluated. The test results revealed that the straight square tool pin profile exhibited a higher ultimate tensile strength of 253 MPa with a tensile elongation of 6.7%. Higher Microhardness and joint efficiency were reported compared to other pin profiles. The microstructures at different zones of the welded joint were examined using optical and scanning electron microscopy. More Flowability indications with fine grain structure were examined for a straight square tool pin profile. The presence of intermetallic and the formation of fine-grain structures were accountable for the improvement in microhardness. The pulsating action of the square pin profile produced a defect-free joint.

Influence of Tool Pin Profile on Mechanical Properties and Microstructure of Friction Stir Welded Aluminium AA7075 Alloy

The present investigation describes the effect of different tool pin profiles on microstructure and mechanical properties of friction stir welded aluminium AA-7075 alloy. The tool pin profiles namely taper cylindrical threaded (TT), cylindrical (CT), square (SQ), triangular (TR), pentagonal (PT), hexagonal (HX) with constant shoulder diameter have been selected to make joints. The friction stir welding was done at constant tool rotational speed and traverse speed. From this study, it is noted that the weld joints prepared using taper cylindrical threaded pin profile exhibited good mechanical properties when compared to other pin profiles. It is due to more surface contact of tool pin and production of equiaxed fine grain structure in the weld region.

Multi objective optimization of process parameters of AA2014 Friction Stir Weldments using Genetic Algorithm

The influence of tool pin profile and process parameters on microstructure and mechanical properties of AA2014 weldments was studied. Tool pin profiles such as a Straight Cylindrical Threaded (SCT) and Taper Cylindrical Threaded (TCT) profiles are used for experimentation. The process parameters such as constant tool rotational speed of 900 rpm, welding speed and tool tilt angles at 30, 40, 50, and 60mm/min and 1o, 2o, respectively, are used to fabricate the weldments. A set of experiments was conducted with two different tool pin profiles and mechanical properties were evaluated. The better mechanical properties such as tensile strength of 367N/mm2, impact strength of 10J and hardness of 139HV were obtained by using TCT pin when compared to SCT pin. The observed mechanical properties have been correlated with microstructure. The mechanical properties were analyzed by ANOVA and regression analysis. Objective functions and constraints are developed for the three responses in terms of factors. The factors are optimized using Genetic Algorithm (GA). From the GA results, it is observed that the welding speed of 58mm/min and tool tilt angle of 1.95o are found to be the better combination for carrying out the experiments using TCT pin profile.

Review on joining of aluminum alloy by solid-state welding technique

FSW is a solid-state welding technique in which no filler material is used to join two similar or dissimilar materials. Welding is performed by a rotating tool, rotation of tool results in a huge amount of friction between shoulder and base material which plays a major role in the joining process. For the welding of 2000, 6000, and 7000 series of aluminium alloys mostly FSW have been preferred over other conventional welding technique such as ARC, TIG, and MIG. Process parameters such as Tool dimension, transverse speed, inclined angle, tool rotation, longitudinal tool force plays a major role in the tailoring of desired mechanical and Microstructural properties, Further investigation on the influence of tool pin profile of these properties are needed. This review paper provides an in-depth discussion about tool profile, microstructure and rotational speed. Also provides existing issues related to welding of metal matrix composite (MMC) and their remedies.

Influence of Tool Pin Profile and Tool Rotating Speed on Mechanical Properties of Al6082 Alloy

Friction stir welding is a solid state welding which uses non consumable welding tool. It is an automatic process which generally performs on the vertical milling machine. In this type of welding, the relative motion between the tools and work piece creates heat which uses the region of work piece to be welded get softened and to joint the two work pieces. Friction stir welding process is more reliable for the materials which are generally non heat treatable. In this present investigation it will observe that how the rotational speeds of the tool and different shapes of the tool pins effects the mechanical properties of the aluminium alloy 6082. For this purpose three tools with different profiles, i.e triangular, cylindrical and square was designed and fabricated. At three different rotational speeds of 560 rpm, 900 rpm, 1800 rpm work pieces are joined using vertical milling machine. Specimens are prepared and tested for mechanical properties, tensile, impact, and hardness tests are performed and to detect the defects and voids x-ray test performed on the weld joints. And it was observed that highest tensile strength was presented when the square pin tool used at 560 rpm. The rotational speed increased mechanical properties are reducing significantly.

Influence of tool pin profiles on friction stir welding with a gap for AA6082-T6 aluminium alloy

In the present experimental study, the influence of tool pin profiles and rotational speeds on friction stir welding joints are studied by the formation of a gap between the abutting plates. Three different tool pin profiles namely plain cylindrical taper, threaded cylindrical taper and straight cylindrical threaded are used to fabricate the joints at the different rotational speeds. The welded joints are visually examined for surface and sub-surface defects. Surface defects such as ripples, small voids and line defects are formed on the surface of welded joints whereas unbounded region and tunnel defects are present in the welded joint with plain and threaded cylindrical taper pin profile tools. Straight cylindrical threaded tool pin profile produces defect free joint with the gap of 1.2 mm in FSW abutting plates.

Influence of tool pin profile and rotational speed on the formation of friction stir welding zone in AZ31 magnesium alloy

In this investigation, the effect of friction stir welding (FSW) parameters such as tool pin profiles, rotational speed and welding speed on the mechanical properties of tensile strength, hardness and impact energy of magnesium alloy AZ31 was studied. The experiments were carried out as per Taguchi parametric design concepts and an L9 orthogonal array was used to study the influence of various combinations of process parameters. Statistical optimization technique, ANOVA, was used to determine the optimum levels and to find the significance of each process parameter. The results indicate that rotational speed (RS) and transverse speed (TS) are the most significant factors, followed by tool pin profile (PF), in deciding the mechanical properties of friction stir welded magnesium alloy. In addition, mathematical models were developed to establish relationship between different process variables and mechanical properties.

Influence of Tool Pin Profile and Welding Parameters on Tensile Strength of Aluminium Alloy 5052 during FSW

The friction stir welding (FSW) is a solid state welding process. It uses non-consumable tool for joining plates with advantages such as low distortion, no shielding gas required and fine recrystallized microstructure. FSW parameters such as tool rotation, welding speed, tool geometry, axial force and tool plunge depth play an important role during welding. In the present work, FSW between the 6mm thick AA5052 aluminium alloy plates was investigated with the combination of two different tool pin profile (Taper Pin-Left Hand Threaded (LHT) and Square Pin) at welding speeds of 30mm/min and 40mm/min with tool rotation speed 850rpm and 1250 rpm. Tensile testing was carried out and comparative study was done to know the best parameter from the selected ones. Maximum tensile strength 378.12 N/mm2 was obtained with taper pin-LHT at welding speed 40mm/min with tool rotation 1250rpm.

Microstructure and static immersion corrosion behavior of AA7020-O Al plates joined by friction stir welding

In the present investigation, the influence of tool pin profile and postweld heat treatment on microstructure, hardness, and static immersion corrosion behavior of AA7020-O Al plates joined by friction stir welding was investigated. Friction stir welding was conducted using two tools having different pin profiles, typically, a tool with tapered cylindrical pin and a tool with two flat-sided cylindrical pin. Postweld heat treatment was carried out using a solution heat treatment temperature of 540 ± 1℃ for 12 h followed by aging at 155 ± 1℃ for 6 h. Corrosion tests were carried out by immersing the welds in an aqueous solution containing NaCl and H2O2 for 6 h according to ASTM-G110. The results revealed that the two flat-sided cylindrical pin tool produces finer α-Al grains, at the center of dynamically recrystallized zones, than the tapered cylindrical pin tool. The postweld heat treatment slightly increases the size of the α-Al grains at the center of dynamically recrystallized zones. In the as-welded conditions, the friction stir welded regions exhibited lower hardness values than the base alloy. However, the regions friction stir welded using two flat-sided cylindrical pin tool showed relatively higher hardness values than those regions friction stir welded using the tapered cylindrical pin tool. The postweld heat treatment slightly increases the hardness of the welded regions to values that are still lower than the base alloy. Generally, the dynamically recrystallized zones are more susceptible to corrosion than the base alloy. In both AW and postweld heat treatment conditions, the thermomechanically affected zones showed the lowest corrosion resistance when compared with dynamically recrystallized zones and heat affected zone regions. In the as-welded conditions, regions friction stir welded using tapered cylindrical pin tool exhibited better corrosion resistance than those friction stir welded using two flat-sided cylindrical pin. The postweld heat treatment improves the corrosion resistance of the dynamically recrystallized zones friction stir welded using two flat-sided cylindrical pin tool.

The effect of pin profiles on the microstructure and mechanical properties of underwater friction stir welded AA2519-T87 aluminium alloy

AA2519-T87 is a new armour grade aluminium alloy employed in the fabrication of light combat military vehicles. Joining of this material using fusion welding processes, results in the formation of solidification defects like porosity, alloy segregation and hot cracking. In order to overcome the solidification related problems, solid state welding processes such as friction stir welding (FSW) can be used. Though the joining takes place below the melting temperature of the material, the thermal cycle experienced by the thermo-mechanical-affected zone (TMAZ) and heat-affected zone (HAZ) is causing grain coarsening and precipitates dissolution in the age-hardenable aluminium alloys, which deteriorate the joint properties. To get rid of this problem, underwater friction stir welding (UWFSW) process can be employed. The water cooling reduces the heat, and thus, the thermal softening required taking place in TMAZ and HAZ. Therefore, the material flow is entirely different in FSW and UWFSW. In this investigation, a comparative study is made to understand the influence of tool pin profiles, namely straight cylindrical (STC), taper cylindrical (TAC), straight threaded cylindrical (THC) and taper threaded cylindrical (TTC) on stir zone characteristics and the resultant tensile properties of both FSW and UWFSW joints. From this investigation, it is found that the joint made by taper threaded pin profiled tool underwater cooling medium exhibited higher tensile properties of 345 MPa and joint efficiency of 76 %. The enhancement in the strength is attributed to the precipitation hardening, grain boundary strengthening and narrowing of lower hardness distribution region (LHDR).

Influence of Tool Pin Profile and Welding Parameter on Tensile Strength of Magnesium Alloy AZ91 During FSW

Magnesium is flammable material and to avoid its limitation of fusion welding solid state welding process, called friction stir welding (FSW), is applied for joining two plates together. The friction stir welding uses a non-consumable tool for joining abutting plates of magnesium alloy AZ91 having 6mm thickness. FSW process joins the plates with advantages such as low distortion, no shielding gas required, and fine recrystallized microstructure. In Friction stir welding, process parameters such as welding speed, tool rotation speed, tool dimensions and axial force play an important role during welding. In the present work, the 6mm thick plates of the said alloy are joined at welding speed of 28mm/min to 56mm/min with tool rotation speed ranging from 710rpm to 1400rpm. Tensile testing was carried out to know the best parameter from the selected ones. Observations are also made for any defects by using fluorescent penetrant testing and photo micrographs.