Effect Of Tool Rotational Speed Research Articles

The effects of tool rotational speed and post-weld heat treatment of friction stir welded AZ31-B magnesium alloy

Abstract This research article examines the effect of increasing the tool rotational speed and post-weld heat treatment behavior of friction stir-welded AZ31-B magnesium alloy. The variable tool rotational speeds of 1000 rpm, 1200 rpm, 1400 rpm, and 1600 rpm with fixed tool traverse speeds of 30 mm min−1 were chosen based on the trial welding method. Results reveal that the as-welded tensile strength values of 133 MPa, 209 MPa, 215 MPa, and 213 MPa for the corresponding tool rotation speeds and post-weld heat-treated tensile strength values of 140 MPa, 213 MPa, 223 MPa, and 227 MPa significantly increased joint strength when compared to the as-welded process. The measured grain size values are reduced when the tool rotational speed increases due to material dynamic recrystallization. Al-Mg brittle intermetallic compounds significantly reduced the mechanical strength during the increase of the tool’s rotational speed. Fractography analysis reveals all welded samples fractured at the center of the stir zone with a ductile fracture angle of 45°.

Effect of Tool Rotational Speed on Microstructure and Mechanical Properties of Friction Stir Welded Al–16Si–4Cu–10SiC Composite/Al–4Cu–Mg Alloy Joints

Effect of Tool Rotational Speed on Microstructure and Mechanical Properties of Friction Stir Welded Al–16Si–4Cu–10SiC Composite/Al–4Cu–Mg Alloy Joints

Effect of tool rotational speed on mechanical and tribological characteristics of friction stir processed CuNi/ZrC surface composites

Effect of tool rotational speed on mechanical and tribological characteristics of friction stir processed CuNi/ZrC surface composites

The Effect of Tool Rotational Speed and Welding Configuration on the Mechanical Properties of High Density Polyethylene (HDPE) Plate Friction Stir Welded Joint

The study investigates the impact of tool rotational speed and welding configuration on the mechanical properties of friction stir welded joints of HDPE plates. The plates were cut into rectangular shapes and clamped on a metal plate for FSW welding. Two welding configurations were used: single-side welding (SS) and double-side welding (DS), with rotational speeds of 900, 1500, and 2000 rpm. The plates were subjected to tensile and bending tests, and angular distortion was also measured. The findings suggest that decreasing the tool's rotational speed to 900 rpm and using double-side welding reduces angular distortion and improves tensile and flexural strength. The study emphasizes the importance of defect reduction techniques in improving the mechanical properties of HDPE FSW joints.

Effect of tool rotational speed on friction stir spot welds of AZ31B Mg alloy to AISI 304 stainless steel

Abstract AZ31B Mg alloy were welded to AISI 304 stainless steel (which is a very challenging task because of their huge different chemical and physical features) by friction stir spot welding (FSSW) at different tool rotation speeds (700, 1000, and 1300 rpm) while keeping other conditions the same. Welds were evaluated and compared by examining their cross-sectional geometry, XRD pattern, tensile shear strength, fracture way and area. From cross-sections of welds, it was obtained that joining area expanded when speed was enhanced and the weld made through 1300 rpm had the largest one. Therefore, weld fabricated with the highest speed of 1300 rpm displayed the biggest tensile shear load of 3741 N while that manufactured with the lowest speed of 700 rpm possessed the lowest of 2430 N. All welds showed tensile shear type fracture and fracture occurred from the hooking regions where joining took place. From the fracture joint region, the weld of 700 rpm had the smallest joined area, whereas that of 1300 rpm showed the biggest. Higher speed produced a stronger joint, which agreed with a bigger bonding area and broken joint region. Also, joint became more ductile with increasing speed. Some phases were detected in joints.

Effect of Tool Rotational Speed and Mechanisms Associated with Microstructure Evolution and Intermetallics Formation in Friction Stir Welding of Aluminum Alloy to Titanium Alloy

Effect of Tool Rotational Speed and Mechanisms Associated with Microstructure Evolution and Intermetallics Formation in Friction Stir Welding of Aluminum Alloy to Titanium Alloy

The Effect of Tool Rotation Speed on the Formation of Eutectic Structure during Friction Stir Welding of Aluminum to Magnesium

Friction stir welding (FSW) is a solid-state welding process capable of joining a wide range of light metals. However, liquation and solidification may occur during joining of dissimilar metals which leads to eutectic formation. This article aims to discover the influence of tool rotation speed on the formation of eutectic structure during friction stir welding of aluminum to magnesium. To do so, friction stir welding was performed at 600 and 950 rpm to join pure aluminum and ECO-AZ91 magnesium alloy in a lap configuration. In order to investigate the influence of the welding speed, the welding speeds of 23.5 and 37.5 mm/min were also chosen. Scanning electron microscopy (SEM) was used to study the microstructure of the joints. A shear-tensile test was used to evaluate the joints’ strengths. The fracture surfaces were also studied by SEM. The results revealed that changing the rotation speed directly affects the eutectic formation, whereas the welding speed had no influence. A lower rotation speed resulted in a thin, continuous intermetallic layer, whereas a higher speed led to the formation of a massive Mg-Al12Mg17 eutectic microstructure. The formation of eutectic, as an indicative of liquation, may affect the material flow during the process due to decreasing the friction coefficient between the tool and material. The macrostructure analyses showed that the phase evolution as well as the mechanism of material flow are highly affected by liquation.

Effect of tool rotational speed on microstructure and mechanical properties of friction stir welded DMR249A high strength low alloy steel butt joints for fabrication of light weight ship building structures

The friction stir welding (FSW) was employed for joining 5 mm thick plates of high strength low alloy steel (HSLA) of grade DMR249A in the development of light weight ship building structures. The main objective of this investigation is to study the effect of tool rotational speed (TRS) on microstructure and mechanical properties of friction stir welded (FSWed) DMR249A HSLA steel butt joints. The indigeneously developed Lanthanated Tungsten alloy (W99) tool was used for FSW of DMR249A HSLA steel plates. The TRS of W99 tool was varied from 500 rpm to 700 rpm while maintaining the remaining parameters at constant level. The microstructure of DMR249A steel joints was characterized using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electron beam scatter diffraction (EBSD) techniques. The elemental analysis of stir zone (SZ) of DMR249A steel-joint was carried out using energy dispersive spectroscopy (EDS). The tensile properties, hardness and impact toughness of DMR249A steel joints were evaluated and compared to base metal (BM). Results disclosed that the DMR249A steel joints made using the TRS of 600 rpm exhibited superior tensile properties and impact toughness compared to other joints. The joints made using the TRS of 600 rpm revealed the greater tensile strength of 664 MPa, yield strength of 502 MPa, elongation of 19% and impact toughness of 48 J. It showed 8.85% and 14.61% improvement in tensile and yield strength along with 20.83% and 22.58% reduction in ductility and impact toughness compared to BM. It is attributed to the evolution of finer acicular ferritic and upper bainitic microstructure with no debris of W99 tool in SZ.

Effects of Tool Rotational Speed on Friction Stir Welded Joints of 1120 Al

Effects of Tool Rotational Speed on Friction Stir Welded Joints of 1120 Al

Development of Aluminium Metal Foams via Friction Stir Processing by Utilizing MgCO3 Precursor

Aluminium foams possess multi-functional properties and a low specific weight, making them one of the most suitable choices in the application domain of the automobile and aviation sectors, vibrating machining, and structural parts. Compared to traditional fabrication routes, friction stir processing (FSP) is gaining acceptance as it is a cost-effective, highly efficient, and innocuous process to fabricate the foam precursors from the bulk substrate. In the current study, FSP was utilized to develop a precursor with MgCO3 powder acting as the blowing agent. The FSP experiments were performed as per Taguchi’s L8 orthogonal array. The precursor was heat treated in an electric furnace at a holding temperature of 650 °C for 10 min. After the post-heat treatments, this precursor resulted in a porous structure due to the evolution of CO2 gas from the composite. The simultaneous effect of tool rotation speed, traverse speed, and shoulder diameter was investigated on the pore size and porosity of the foam produced. The composite parameter “unit stirring” is found to be closely related to the processed zone (PZ) and volume processing rate of the processed zone, pore size, and the degree of porosity. The highest porosity of 16.67% was obtained with an average pore size of 10.5 µm. The largest pore size, 17.8 µm, was observed to be associated with a porosity of 14.40%. The analysis of the Kiviat plot revealed that the values of the PZ area and volume processing rate possess a polar symmetry with unit stirring. The pore size and pore density were both found to be symmetrically distributed about the unit stirring.

Effect of tool rotation speed on microstructure and mechanical properties of underwater friction stir welding 6061 aluminium alloy

This work presents the experimental investigation of the effect of tool rotation speed (TRS) on the mechanical properties of the 6061-T6 aluminium alloy weld joint in the underwater friction stir welding (UFSW) process. The experiments are conducted with four different TRS, 710, 900, 1120, and 1400 rpm, and a constant welding speed (WS) of 20 mm/min, respectively. The welding is performed under the water in the butt joint configuration on the vertical milling machine (Model HMT FN2H). The experimental result shows that the average grain size decreases and tensile strength and hardness increases on increasing the TRS up to mid-range of the TRS and further increasing the TRS the trend of grain size and tensile strength and hardness are increases and decreases, respectively. The maximum tensile strength value is 190 MPa, and the minimum grain size is 5 µm at 1120 rpm. Additionally, the optimum condition of tensile strength and weld zone shape is compared with the conventional friction stir welding process, and it is found that tensile strength is increased by 20% and smaller weld zone shape are observed in underwater friction stir welding process. The brittle fracture dominance is observed at lower TRS and ductile dominance fracture in 900, 1120, and 1400 rpm of the weld joint.

Optimizing the process parameters of Fiction Stir Welded dissimilar 2024Al-5754Al Joint using the Taguchi Method

It is a requirement of modern age industries, especially the aerospace, automobile, and shipbuilding sectors, to manufacture high strength and low weight dissimilar aluminium alloy welded joints. Therefore, the aim of this project is to investigate the effect of tool rotation speed, feed rate, and pin type on the ultimate tensile strength (UTS) of dissimilar aluminium alloys (2024 Al and 5754 Al) in friction stir welded joints. Nine experiments have been performed using an orthogonal array (L9) of the Taguchi method. An analysis of variance (ANOVA) established that pin type is the most prominent parameter, followed by tool rotation speed and feed rate. The optimal value of ultimate tensile strength (268 MPa) was achieved at 1.5 mm/s feed rate, 1600 rpm speed, and type 1 of pin. A confirmation test shows that there is a high correlation between the estimated and actual values of UTS.

Effect of tool rotation speed on mechanical properties of underwater friction stir welding of 6061-T6 and 5083-H12 aluminium alloys

This work presents an experimental investigation of the effect of tool rotation on the mechanical properties of 6061-T6 and 5083-H12 aluminium alloys in the UFSW weld joint. The experiments are conducted in a vertical milling machine (model no. HMT FN2H) at four different tool rotation speeds (TRS), such as 710, 900, 1120, and 1400 rpm, at constant welding speed (WS) of 63 mm/min. The welding was performed under the water in the butt joint configuration in which the 6061-T6 workpiece material is placed on the retreating side (RS) and 5083-H12 on the advancing side (AS). The results show that the performance of the weld joint quality depends on the TRS. The shape and size of the weld nugget zone (WNZ) and thermo-mechanically affected zone (TMAZ) increase with increasing the TRS. The tensile strength of the weld joint and average grain size of the stir zone (SZ) increases and decreases respectively on increasing the TRS 710 to 1120 rpm. Further increasing the TRS, the tensile strength of the weld joint and average grain size of SZ decreases and increases respectively. Additionally, the fracture surface shows the brittle dominance fracture mode at 1400 rpm, and 710 to 1120 rpm weld joints show the ductile fracture mode.

Pre-weld friction stir processing enabling strong and ductile fusion welds on AZ91 magnesium alloy

Liquation in the partially melted zone (PMZ) is the critical weldability issue of cast AZ91 magnesium alloy. Friction stir processing (FSP) is used as a local pre-weld treatment to create a local liquation-resistant microstructure in cast AZ91 alloy during arc welding. The effects of tool rotational speed during pre-weld FSP on the liquation-related microstructural features (i.e. grain structure, size and volume fraction of eutectic β-Mg17Al12) and the liquation characteristics of the fusion-welded AZ91 (i.e. PMZ size and grain boundary liquid film thickness) were investigated. The pre-weld FSP treatment of the cast AZ91 significantly improved the tensile strength and ductility of the welds mainly due to significant reduction in the thickness of the re-solidified eutectic β-Mg17Al12 film in the PMZ.

Effect of tool rotational speed on microstructure and mechanical properties of AA6061/SiC surface composites using friction stir processing

An investigation was conducted into how the tool rotation speed affected the microstructure and mechanical properties of friction stir processed samples based on AA6061-T6/SiC surface composites. The tool rotated between 700 and 1500 rpm with steps 400 rpm, while the other process variables were kept constant. Visual inspection reveals a sound and defect-free weld surface. The microstructure and particle dispersion of composite surface based on synthesis of aluminium alloys were revealed using an optical microscope. The findings demonstrate that rotational speed has a substantial impact on the uniform dispersion of SiC particles, which were observed at 1100 rpm found that refined and uniform distribution of particles as compared other rotational speeds. At tool rotational speed (TRS) of 1100 rpm, the friction stir processed specimen's microhardness and tensile strength, which seem to be 128 HV and 305 MPa, respectively.

Development of AA6061/316 stainless steel surface composites via friction stir processing: Effect of tool rotational speed

Metallic and alloy particles are recognized as alternatives to ceramic reinforcements to improve the overall characteristics of Al metal matrix composites. The present study aimed to investigate the friction stir processing/manufacturing of the 316 stainless steel particles reinforced AA6061 Al matrix composites by varying the tool rotational speeds. The microstructure, tensile, hardness, wear, corrosion behavior, and shear punching tests of the composites were studied. The results showed that the friction stir processing route produced no particle-matrix reaction in the composite and dislocation entanglements were formed close to the inherent 316 stainless steel particles within the Al matrix. The improved mechanical action of the tool aided particle fragmentation as the average 316 stainless steel particle sizes decreased from 41.88 to 26.89 μm. As a result of the dynamic recrystallization and particle-assisted pinning effects, the mean grain sizes of the composite decreased from 7.48 to 4.31 μm when the tool rotational speed was raised. An increment in the tool rotational speed (800–1200 rpm) triggered a rise in the maximum shear force (1198–1562 N), tensile strength (200.09–279.98 MPa), and maximum hardness value (121–139 HV) of the composite while a favorable decrease in the composite's wear rate (0.63–0.20 mg/m) and the friction coefficient (0.38 ± 0.01–0.21 ± 0.01) ensued. The composite's improvement is attributable to the homogeneous spread of dislocation.

Effects of parameters on friction stir welding process of AA 7075 aluminum alloy: mechanical and microstructural assessments

AbstractThe effect of tool rotation speed and welding speed on the microstructural and mechanical properties of AA 7075‐T651 welded plates produced using friction stir welding is the research subject of this study. A basin‐shaped stir zone characterized all friction stir welded joints’ microstructures. The fracture location following the tensile test was found to be outside the stir zone for each welded joint. All welded joints were subjected to a 90° root bending test. The tests were terminated before each welded joint could reach the 90° bend angle in the stir zone. The stir zone of each welded joint was characterized by the fine and equiaxed grains with the effect of dynamic recrystallization. In addition, intermetallic particles were also detected to occur in the weld joint. Among the nine welded joints, the welded joint with the highest ultimate tensile strength of 382 MPa was produced with a tool rotation speed of 400 min−1 and a welding speed of 80 mm min−1. The highest welding efficiency of 71 % was obtained with the welding process parameters of 400 min−1 tool rotational speed and 80 mm min−1 welding speed. Increasing tool rotation speed caused the grain size to be coarser.

Microstructure and mechanical performance of dissimilar friction stir spot welded AA2024-O/AA6061-T6 sheets: Effects of tool rotation speed and pin geometry

Nowadays, friction stir spot welding (FSSW) is becoming a serious candidate technology to join aircraft materials such as AA2024-O and AA6061-T6 since the use of FSSW offers significant weight savings compared to a conventional riveting technique. However, some issues, especially related to mechanical properties of FSSW joints still exist. To address these problems, the present investigation aims to study effects of tool rotation speed and pin geometry on microstructure and mechanical strength of dissimilar friction stir spot welded AA2024-O/AA6061-T6 joints. The welding processes were conducted using two different tool pins, namely cylindrical and stepped pins at varying tool rotation speeds of 900 rpm, 1400 rpm and 1800 rpm. Subsequently, experimental works including microstructural observation, microhardness measurements, lap shear tests combined with fractography analysis were conducted. Results showed that an increase in tool rotation speed resulted in microstructural coarsening in stir zone (SZ). In addition, the tool rotation speed together with the pin affected the material flow hence hook characteristics. It was found that the dissimilar friction stir spot AA2024-O/AA6061-T6 welded joint having excellent lap shear failure load (LSFL), typically 4468.4 N was produced using a cylindrical pin at the tool rotation speed of 1400 rpm. Under this lap shear testing, the mode of failure changed from shear to mixed mode failure as the tool rotation speed was increased. It seemed that hook characteristics, grain size and precipitation hardening were the key factors influencing the weld mechanical properties.

Modeling and optimization of friction stir stitching of AISI 201 stainless steel via Box-Behnken design methodology

Abstract The paper investigates the modelling and optimization of the notch-repaired/friction stir stitched AISI 201 stainless steel welds via the use of a non-consumable tool-based repair process. The repair process employs a sequential hopping-stitching approach. This approach involves the application of two intercepted and completely overlapped plunging actions of a probe-less titanium carbide tool to create an effective refilling and repair of the notched zone. Box-Behnken design (BBD) was employed for the experimental planning, modelling, and optimization of the notch-repair process. Tool rotational speed, penetration depth and dwell time of the tool were the studied process parameters while tensile strength was the response variable. A quadratic model was identified as the best model for the notch-repaired welds based on the combination of a low sequential P-value of 0.008216, a high lack of fit P-value of 0.931366, and a close to unity adjusted and predicted R-square values. The process parameter and their interaction effects on the tensile strength of the repaired notch were identified via the ANOVA analysis. Plunge depth (main effect) and interaction effect of tool rotational speed and dwell time had significant influences on the notch-repair process and the resultant tensile strength of the AISI 201 stainless steel. The visual representations of these effects were shown through the 2D elliptical contour and 3D response surface plots. The optimized process parameters were identified as 1215.9795 rpm, 0.40262212 mm, and 5.98706376 s while the resultant notch-repaired joint yielded a tensile strength of 886 MPa, which is close to the predicted value.

Effect of tool rotational speed and position on mechanical and microstructural properties of friction stir welded dissimilar alloys AZ31B Mg and Al6061

Abstract The existence of some problems in joining Al and Mg alloys using classical fusion welding methods causes limitations in the use of Mg and Al alloys in common structures. Friction stir welding (FSW) is a solid-state welding method for joining materials having same or different properties at temperatures below their melting points. In this study, dissimilar alloys AZ31B Mg and Al6061 were joined by FSW at a feed rate of 34 mm·min−1 and at different tool rotational speeds (600 and 700 rpm) and material positions. During the welding process, AZ31B Mg plate was positioned at the advancing side and Al6061 was located at the retreating side, and moreover, the two alloys were also positioned vice versa. Tensile strength and microhardness tests were performed to examine the mechanical properties of the welded specimens. The microstructures of the welded zones were examined by obtaining the optical microscopic (OM) and scanning electron microscopic (SEM) images. The highest welding strength was obtained from the specimen welded at a tool rotational speed of 600 rpm, at a feed rate of 34 mm·min−1 and by locating AZ31B Mg on the advancing side.