Tool Rotational Speed Research Articles

Tribological Behavior of Friction Stir Processed Nanocomposite Prepared Through Self-Assembled Monolayer Technique

Abstract An attempt was made to use friction stir processing, a manufacturing technique usually employed for the fabrication of nanocomposites. For the substrate, AA7075 was used and for dispersed phase, B4C nanoparticles of size (<30 nm) were selected. Nanocomposite samples were fabricated using three different tool rotation speeds of 1000, 1200, and 1400 rpm, by keeping other process parameters as constant, and their influence on the nanocomposite was judged by the study of tribological behavior and microhardness. This research work aims at the self-assembled monolayer formation of B4C nanoparticles homogeneous layer into a substrate material and hence minimizing the quantity of nanoparticles required in the preparation of nanocomposites via FSP. The results in terms of increased microhardness compared to the substrate material are reflected by the sample processed at the tool rotation of 1200 rpm. The average microhardness was found out to be 195 Hv compared to the substrate material. There is a maximum increment attained in wear resistance upto 46.7% in the sample processed at 1200 rpm. Worn out surface morphology were analyzed through scanning electron microscopy, and X-ray diffraction was also undertaken to analyze the presence of reinforcement particle in the fabricated nanocomposites.

Fabrication of three-layered aluminium-copper laminated composites using friction stir additive manufacturing

Abstract The current study employed the friction stir additive manufacturing (FSAM) method to fabricate three-layered laminated composite by utilizing 3 mm thick sheets of AA6061-T6 alloy (top and bottom layers) and pure Cu (middle layer). The feasibility of FSAM in producing high-performance Al/Cu/Al laminated composites was evaluated by analyzing the influence of tool rotational speed on the microstructure and mechanical properties. The composites were fabricated at rotational speeds of 900 rpm, 1200 rpm, and 1500 rpm; maintaining a traverse speed of 90 mm min−1 throughout the experiments. Changes in the weld morphology, macrostructure, microstructure, and intermetallic formation were noted and analyzed. The findings indicated that achieving macro defect-free joints is possible with a rotational speed of 1200 rpm. Detailed examinations via electron dispersive spectrum and x-ray diffraction revealed the presence of AlCu, Al2Cu and Al2Cu3 intermetallic compounds within the nugget zone. Significantly varied microhardness levels ranging from 59.4 to 143.7 HV0.1 were observed, corresponding to distinct microstructural features within the processed zone. The Al/Cu laminated composite exhibited an excellent combination of strength and ductility; a UTS of 214.6 MPa and an elongation of 23.4%. The findings showcase that utilizing FSAM presents an exceptional opportunity to fabricate novel Al/Cu multilayered composites with distinctive mechanical properties.

Microstructure, microhardness and wear properties Investigation in Friction Stir Processing of Stir Cast Mg/B4C metal matrix composite

Abstract Friction Stir Processing (FSP) has emerged as an excellent processing approach to tailor the microstructural and other properties of cast alloys and composite materials. In the current investigation, a stir-cast magnesium metal matrix composite (MMMC) reinforced with 12 wt% B4C particles was processed using single-pass FSP. FSP was carried out with a simple cylindrical tool pin using different tool rotational speeds of 800, 1000, 1200 rpm and transverse speed of 60 mm/min. Severe deformation occurred during FSP which helped to refine the distribution of the B4C particles and grain refinement of as-cast composites. Microstructural examination showed an appreciable grain refinement from 98 to 5μm because of dynamic recrystallization during FSP. The maximum microhardness of the friction stir processed (FSPed) composites increased from 73 Hv to 105.4 Hv. Pin-on-disk wear tests were conducted under dry sliding conditions in the load range of 1 kg to 5 kg at a 1 m/s sliding velocity. The wear results indicated an enhancement of wear properties of FSPed composites in comparison to as-cast magnesium metal matrix composites. The improved hardness and wear resistance results were pertaining to the remarkable refinement in grain size coupled with refined B4C particulates and uniform distribution. The best results for hardness and wear resistance of the FSPed composite were obtained for a sample processed at a tool rotation speed of 1000 rpm. SEM/EDS of the worn samples was carried out. The wear mechanism was found as slight abrasion and oxidation. After single pass FSP, the surface of Mg/12wt% B4C cast composite showed remarkable changes in worn surface morphology.

Microstructure, microhardness and wear properties Investigation in Friction Stir Processing of Stir Cast Mg/B4C metal matrix composite

Abstract Friction Stir Processing (FSP) has emerged as an excellent processing approach to tailor the microstructural and other properties of cast alloys and composite materials. In the current investigation, a stir-cast magnesium metal matrix composite (MMMC) reinforced with 12 wt% B4C particles was processed using single-pass FSP. FSP was carried out with a simple cylindrical tool pin using different tool rotational speeds of 800, 1000, 1200 rpm and transverse speed of 60 mm/min. Severe deformation occurred during FSP which helped to refine the distribution of the B4C particles and grain refinement of as-cast composites. Microstructural examination showed an appreciable grain refinement from 98 to 5μm because of dynamic recrystallization during FSP. The maximum microhardness of the friction stir processed (FSPed) composites increased from 73 Hv to 105.4 Hv. Pin-on-disk wear tests were conducted under dry sliding conditions in the load range of 1 kg to 5 kg at a 1 m/s sliding velocity. The wear results indicated an enhancement of wear properties of FSPed composites in comparison to as-cast magnesium metal matrix composites. The improved hardness and wear resistance results were pertaining to the remarkable refinement in grain size coupled with refined B4C particulates and uniform distribution. The best results for hardness and wear resistance of the FSPed composite were obtained for a sample processed at a tool rotation speed of 1000 rpm. SEM/EDS of the worn samples was carried out. The wear mechanism was found as slight abrasion and oxidation. After single pass FSP, the surface of Mg/12wt% B4C cast composite showed remarkable changes in worn surface morphology.

Residual Stress in Friction Stir Welding of Dissimilar Aluminum Alloys: A Parametric Study

Welding-induced residual stress has the capacity to significantly compromise the integrity of mechanical components. Its minimization therefore plays a critical role in the selection of process parameters during the welding process. Friction stir welding is a useful joining technique to weld many materials that are not amenable to the traditional welding techniques. Using a sequentially coupled thermomechanical three-dimensional finite element simulation, this work aimed to quantitatively evaluate the influence of the tool rotational and traverse speeds on the generation of residual stress in the friction stir welding of dissimilar aluminum alloys AA2024−T3 and AA5086−O. The model was validated using established experimental and numerical results. The procedure entailed an initial thermal analysis, the results of which were superposed on a mechanical model to determine the distribution of the residual stress across the welded alloy. The results showed that longitudinal residual stress was dominant as compared to lateral stress. It was also demonstrated that, although the tool rotational speed and the tool traverse speed both affected the post-weld temperature distribution and consequently the longitudinal residual stress, the influence of the former was more substantial. Furthermore, the peak values of the residual stress were found on the retreating side (AA5086−O), making it more critical for the selection of welding process parameters.

Finite element modeling of microstructure evolution and bonding during Friction Stir Extrusion of AA6061 powder at different tool feed rates and rotational speeds

Finite element modeling of microstructure evolution and bonding during Friction Stir Extrusion of AA6061 powder at different tool feed rates and rotational speeds

Influence of Grinding Tool Mesh Size and Rotational Speed on Post-Machining Quality of CFRP Laminates by Acceleration Signal and Surface Roughness Analyses

In the grinding process, acceleration signals in both the time and frequency domains are valuable for monitoring and controlling vibration patterns, as factors such as rotational speed and the grinding head design significantly influence machining quality, efficiency, and finishing performance. This study analyzes the acceleration signals by dividing them into three distinct stages, pairing this analysis with microscopic morphology to investigate the grinding behavior of carbon fiber-reinforced polymer (CFRP). The findings reveal that high-frequency and low-amplitude vibrations enhance polishing efficiency and quality, whereas low-frequency and high amplitudes adversely affect grinding quality. Acceleration vibrations are more stable during the intermediate grinding stage compared to the initial and final stages, which helps reduce surface roughness, regardless of the rotational speed or grinding head mesh size. In addition, a coarse mesh (#40) results in an uneven surface due to a large amount of removed material, whereas a fine one (#120) results in lower material removal but continuous vertical vibrations due to the impact with the grinding surface, also resulting in poor surface quality. Thus, controlling the tool’s size and rotational speed is essential in reducing the amplitude of the vibration, allowing for maximizing the grinded CFRP surface quality.

Shape Accuracy Improvement of the Flange Turning Process in Aluminum Aerosol Can Production

This study investigates the flange turning process in the production of aluminum aerosol bottles. Aluminum discs are lubricated, extruded, trimmed, washed, painted, and lacquered before undergoing necking, where flange turning ensures a secure, aesthetically pleasing fit. Errors in flange turning, such as uneven or tapered surfaces, can compromise bottle functionality and appearance. To address this, experiments were performed with different tool geometries, feed rates, and rotational speeds. The investigations aimed to achieve flat, consistent flange surfaces with minimal deviation from the desired geometry. Two main variables were examined: a 1 s waiting time at the end position and variations in feed rate and cutting depth. The waiting time improved flatness, halving surface deviations, while regrinding the tool reduced flatness errors to a tenth of the original values. Higher feed rates and speeds also enhanced surface quality, with flatness errors ranging from 371 μm to 75 μm. Overall, this study demonstrates that optimizing parameters like cutting angle, feed rate, and rotational speed, along with a waiting period, significantly enhances surface accuracy. These findings support more efficient production processes for aluminum aerosol bottles.

Effect of Rotational Speed on Mechanical Properties of AA5083/AA6082 Friction Stir Welded T-Joints for Naval Applications

This study evaluates the influence of rotational speed on the mechanical and microstructural properties of T-joints fabricated via friction stir welding (FSW) using dissimilar aluminum alloys, AA5083 and AA6082, for naval applications. Three types of joints were produced by maintaining a constant traverse speed of 100 mm/min and varying the tool rotational speed at 500, 700, and 900 rpm. Mechanical performance was assessed through pull-out tests and microhardness measurements. The joints fabricated at 500 rpm demonstrated superior mechanical properties, including a more uniform hardness distribution and higher pull-out strength, attributed to optimized material mixing and heat input at this speed. In contrast, higher rotational speeds led to defect formation, such as wormholes, and compromised mechanical performance. These findings underscore the importance of optimizing rotational speed to enhance joint quality, making FSW a viable solution for manufacturing durable, lightweight structures in demanding marine environments.

Investigation of Microstructure and Mechanical Properties of Al Alloys Lap Joints by Friction Stir Welding

An experimental investigation on effect of friction stir lap welding (FSLW) process parameters on mechanical and microstructure of AA6082-O welds is presented. Three process parameters namely tool rotational speed (1000,1400 & 2000 rpm), tool shoulder diameter (18, 20 & 22 mm) and tool traverse speed (28, 56 & 80 mm/min) are considered. Experiments are planned as per L9 Taguchi array. Data are analyzed in terms of S/N ratio and Analysis of Variance (ANOVA). Tensile shear strength is observed in the range of 11.79 MPa to 29.23 MPa. It is observed that tool diameter and tool rotational speed are most significant factors affecting tensile shear strength. Optimum levels of process parameters (28 mm/min tool traverse speed, 18 mm tool diameter and 1400 rpm tool rotational speed) is decided based on analysis of experimental data. Using optimum process parameters for friction stir lap welding of Al alloys improved quality of welded joints can be made. Use of optimized parameters will improve the performance of the products in terms of durability and load carrying capacity.

Joining of thin aluminum sheets by micro-friction stir welding (μFSW) using a pinless tool

Abstract In the present research, butt welding of 0.8 mm thick aluminum 6061–T6 sheets has been executed using a pinless tool with variable tool rotational speed (1000-2500 rpm), welding speed (100–250 mm min−1), and a constant plunging depth (0.1 mm). Tensile and microhardness tests have been conducted to evaluate the joint’s mechanical strength. The joint developed at 2500 rpm, and 100 mm min−1 shows a maximum strength of 277.65 MPa (88.4% of original strength), indicating that higher tool rotational speed and slower welding speed enhance joint formation through adequate heat generation and material intermixing. Small amount of defects like flash, surface galling, and irregular shoulder marks have been found in the weld region.

Experimental investigation of tool geometries on Al/Cu dissimilar friction stir welded joint for varying rotational speed

The present study investigates the effect of geometrical alterations (straight cylindrical threaded and straight hexagonal) on the heat input and the resulting weld formation, microstructure, and mechanical properties of the tool for varying rotational speeds. A detailed SEM-EDS analysis is employed at Al–Cu interface to study the formation of various intermetallic compounds and their distributions. The line EDS results at Al-Cu interface show a clear junction at a very narrow region for 1200 rpm for both tools. The total heat input for a threaded cylindrical tool at 1200 rpm was the highest however the diffusion of Cu into Al was poor and attained the lowest tensile strength. At 1400 rpm besides the bulk movement of Cu at the top, fine distribution Cu particles with Al2Cu, Al + Al2Cu intermetallic compounds were also observed at stir zone for straight hexagonal tool and resulted in the highest tensile strength. It is found that straight hexagonal tool attains improved tensile strength than straight cylindrical threaded tool irrespective of tool rotational speeds. At 1400 rpm total heat input remains unaffected by the tool geometry and bead appearance also improves irrespective of tool geometry.

Experimental investigation and parametric optimization of FSW of mineral-reinforced AA6061 matrix composite

Abstract In this work, rutile reinforced AA 6061 matrix composites were joined using friction stir welding and the process variables were optimized using Taguchi L27 orthogonal design of experiments. The rotational speed, axia force and tool tilt angle were the parameters taken into consideration. The optimum process variables were determined with reference to tensile strength, impact strength and hardness of the joint. The predicted optimal value of output responses were confirmed by conducting the confirmation run using optimum parameters. The optimal process variables combination values that resulted in improved mechanical properties were observed at a tool rotational speed of 1400 rpm, a tool tilt angle of 2 degree, and an axial force of 3KN. Scanning electron microscopy (SEM) analysis were used to probe the microstructures.

Fatigue life of friction stir spot welds between Z91 magnesium alloy and ENAW7075-T651 aluminum alloy

Abstract Magnesium (Mg) and aluminum (Al) alloys are considered to be among the lightest structural metals. Using these materials in a design can considerably decrease weight, which brings many benefits like reducing fuel consumption and increasing the performance of an aircraft or a ground vehicle. However, these alloys are too difficult to be joined via fusion welding techniques. In this context, welding AZ91 Mg alloy to ENAW7075-T651 Al alloy by the solid-state welding method of friction stir spot welding was investigated comprehensively. These alloys were welded by utilizing a tool with a triangle pin and various tool rotational speeds (1,000, 1,400, and 1,800 rpm) and welding times (3 and 6 s). Macro and microstructure of the welds and their hardness, tensile strength, and tension-compression fatigue life were determined. Generally, an improvement in the mechanical properties of the weld was observed by increasing the welding time due to the expansion of the joining area. The welding with the best mechanical properties was obtained at 1,400 rpm, and the worst at 1,800 rpm. All the welds failed from the weld area during the tensile and fatigue tests and exhibited a brittle fracture mode due to the formation of intermetallic compounds in the welds.

Effect of tool rotation and welding speed on microstructural and mechanical properties of dissimilar AA6061-T6 and AA5083-H12 joint in friction stir welding

Abstract The study investigates joining AA6061-T6 and AA5083-H12 aluminum alloys, each 6 mm thick, in a butt joint. It aims to analyze the impact of varying input parameters on the microstructural and mechanical properties of the joints. Three tool rotation speeds (900, 1,120, 1,400 rpm) and welding speeds (40, 63, 80 mm min−1) are examined. Temperature in the weld zone correlates with tool rotation speed positively and welding speed inversely. Initially, the average grain size in the stir zone decreases with increasing tool rotation (900–1,120 rpm) and welding speed (40–63 mm min−1), then increases with further increments (1,400 rpm, 80 mm min−1). Tensile strength increases by 7 % from 900 to 1,120 rpm but decreases by 19 % at 1,400 rpm. Similarly, it rises by 14 % from 40 to 63 mm min−1, then decreases by 6 % at 80 mm min−1. Optimal mechanical properties occur at 1,120 rpm and 63 mm min−1, with ductile mode failure identified in joints with higher efficiency.

Multiresponse optimization applied to friction-stir processing to enhance wear and corrosion performance in Al–Si alloys

In this study, friction stir processing (FSP) parameters were optimized using the response surface method (RSM) to enhance hardness, reduce the friction coefficient and minimize the corrosion rate in cast Al12Si and Al14Si alloys. The FSP tool, made of AISI H13 tool steel, features a concave shoulder and conical pin designed to induce severe plastic deformation. Microstructural analysis was performed via optical microscopy and SEM–EDS, and the particle size and distribution were assessed via ImageJ software. Microhardness profiles were measured across the Nugget, TMAZ, HAZ, and substrate zones. The corrosion resistance was evaluated using an AutoLab potentiostat/galvanostat following ASTM G59-97 standards, whereas the wear performance was assessed using a reciprocating linear tribometer (ASTM G133). FSP led to the fragmentation and uniform distribution of silicon and Fe-rich intermetallic phases within the aluminum matrix. The multiresponse optimization identified the optimal FSP parameters for Al12Si alloys at a tool rotation speed of 1100 rpm and a travel speed of 16 mm/min. Under these conditions, the Al12Si samples presented the highest microhardness (93 Hv), significant fragmentation of silicon particles (2.82 μm) and Fe-rich intermetallic phases (2.07 μm), reduced friction coefficient (0.60) and low corrosion rate (1.28 × 10⁻4 mm/y). The proposed model offers a reliable method to optimize FSP, leading to aluminum surfaces with superior microstructure, hardness, wear resistance and corrosion resistance.

Investigation of the Weldability of 3D-Printed Multi-Material Materials (PLA and PLA Wood) Using Friction Stir Welding.

In the industry sector, it is very common to have different types of dissimilar materials on the same construction rather than products made from a single type of material. Traditional methods (welding, mechanical fastening, and adhesive bonding) and hybrid techniques (friction stir welding, weld bonding, and laser welding) are used in the assembly or joining of these materials. However, while joining similar types of materials is relatively easy, the process becomes more challenging when joining dissimilar materials due to the structure and properties of the materials involved. In recent years, additive manufacturing and 3D printing have revolutionized the manufacturing landscape and have provided great opportunities for the production of polymer-based multi-materials. However, developments in the joining of multi-material parts are limited, and their limits are not yet clear. This study focuses on the joining of 3D-printed products made from PLA-based multiple materials (PLA and PLA Wood) using friction stir welding. Single-material and multi-material parts (with 100% infill ratio and three different combinations of 50% PLA/50% PLA Wood) were welded at a feed rate of 20 mm/min and three different tool rotational speeds (1750, 2000, and 2250 rpm). Tensile and bending tests were conducted on the welded samples, and temperature measurements were taken. The fractured surfaces of the samples were examined to perform a damage analysis. It is determined that the weld strength of multi-materials changes depending on the combination of the material (material design). For multi-materials, a welding efficiency of 74.3% was achieved for tensile strength and 142.68% for bending load.

Parameter Optimization for Dissimilar Aluminum Alloys Joined Using Friction Stir Additive Manufacturing: A Screening Study

ABSTRACTDue to the requirement for better strength‐to‐weight ratios, the utilisation of aluminum alloys is rapidly expanding. Lightweight components are of utmost importance in most industries, particularly in transportation, aviation, maritime, automotive, and other industries. These lightweight engineering materials are hard to be joined utilising traditional fusion joining techniques, necessitating the development of alternative joining techniques. The novel friction‐stir additive manufacturing (FSAM) technique, based on the concept of friction stir welding (FSW), can be used to combine aluminum alloys additively in their solid state. This work examines the effects of several process parameters (tool rotational speed, tool tilt angle, and tool transverse speed) on tensile strength and hardness using a 3‐factor L9 Taguchi designed experiment. Three cases were explored, one were AL 6061 was welded to AL 7075, one where AL 7075 was welded to AL 6061, and one where the data were mixed to get an “average” effect representative of large additively manufactured parts. A detailed ANOVA (including both main effects and interactions analyses) provided clear guidance on the optimization of the parameters for several objectives. This work will contribute to the development and wider use of FSAM in both industrial and academic research settings by providing a useful dataset and clear parameter selection guidance. The results of this research indicate that the FSAM methodology could be utilized to fabricate large defect‐free structures, which can be a suitable replacement for the traditional Al6061 material used in automotive and aerospace sectors.

Friction Stir Extrusion: Parametrical Optimization for Improved Al-Si Aluminum Tube Production

Friction Stir Extrusion (FSE) was employed to convert cylindrical LM13 ingots into pipes, utilizing three distinct designs of rotating tool heads. This study examined the influence of process variables, consisting of tool rotational speed and plunging speed, on key properties of the resulting products. The properties investigated encompassed the size of Si precipitates, microhardness, wear resistance, and ultimate compressive strength (UCS). To effectively establish the relationships between the process input variables and the resulting mechanical and microstructural characteristics of the produced pipes, an artificial neural network (ANN) was used. This established correlation was integrated into a hybrid multi-objective optimization framework to identify the optimal process parameters. The investigation determined the ideal configuration: a plunging rate of 31 mm/min, a rotational rate of 653 rpm, and tool design number 3.

Investigating the Surface Quality of Aramid Honeycomb Materials Through Longitudinal–Torsional Ultrasonic Milling

During the milling process of aramid honeycomb, residual stresses arise, which will affect the surface quality of the honeycomb. Studies have shown that reasonable processing techniques can reduce residual stresses, indicating a close relationship between residual processing stresses and the processing parameters, such as technique. By investigating the changes in residual stresses after the processing of aramid honeycomb materials, the influence of processing techniques on these changes is analyzed. Leveraging the correlation between residual stresses and surface quality, this study proposes the use of residual stress as an indicator for evaluating processing techniques. The longitudinal–torsional ultrasonic vibration milling method is applied to the processing of aramid honeycombs. A single-factor experimental approach is adopted, utilizing ABAQUS 2020 software to mimic the longitudinal–torsional ultrasonic milling process. This study explores the influence patterns of various process parameters on the residual stresses generated during the milling of honeycombs. The simulation results indicate that within the selected range, the residual stress decreases as the tool rotation speed increases, while it increases with the increase in feed rate. The influence of milling depth on residual stress can be negligible. Furthermore, experiments were conducted based on the proposed correlation between residual stress and surface quality. The experimental results show good agreement with the simulation results, indicating that under reasonable process parameters, the residual stress values decrease, thereby improving the milling surface quality of aramid honeycomb materials. Therefore, measuring residual stress can serve as an effective method for evaluating the processing technique.