Friction Stir Processing Method Research Articles

The Use of Ashes in Surface Metal Matrix Composites Produced by Friction Stir Processing

The article presents an assessment of the possibility of using ashes from the combustion of coal and biomass as a reinforcing phase in metal matrix composites. The composite surface layer was produced by means of the FSP (friction stir processing) method, using an original hole solution with a shifted working zone of the pin. The composite matrix was AA7075 alloy. The obtained composite was subjected to microscopic observations, tribological tests, and hardness measurements. The microscopic examinations revealed favorable changes in the microstructure, in particular, strong refinement of the grains, uniform distribution of the reinforcing phase, and good bonding of the particles of this phase with the matrix material. Changes in the microstructure resulted in a significant increase in the hardness (from 36 to 41% depending on the type of reinforcing phase) and wear resistance (from 24.1 to 32.9%), despite partial dissolution of the intermetallic phases. It was found that the effect of strengthening the matrix and the uniformity of the distribution of the reinforcing phase depend on the physicochemical properties of the used powders, especially on the shape and size of the particles. The research shows that the use of ashes as a reinforcing phase in composites is fully justified.

Effect of Yttria-Stabilized Zirconia addition along with Cu in development of titanium based metal matrix composite via FSP technique for the application in biomedical devices

ABSTRACT The present study investigated the effect of incorporating Yttria-Stabilized Zirconia (YSZ) and copper (Cu) in the development of Titanium-Based Metal Matrix Composites (TMCs) using the Friction Stir Processing (FSP) technique. The macrostructure of the TMCs, after adding 5% YSZ and 2% Cu, displayed a defect-free, crack-free, and porosity-free surface, indicating the precision of the FSP method. Microstructure analysis revealed a uniform distribution of reinforcement particles and proper dispersion of grains, key for enhancing mechanical properties. The interfacial bonding between titanium and YSZ was exceptionally strong, devoid of cracks and porosity, attributed to the copper additive’s role. The increase in the number of grains per square inch for the Ti/5% YSZ/2% Cu composite (1176.26 grains per square inch at 500×) signified finer grain structure, contributing to a remarkable 48.04% improvement in tensile strength compared to pure titanium. The uniform distribution of reinforcement and strong bonding between titanium and YSZ are the driving forces behind the 46.34% increased in hardness. Additionally, the wear resistance of the composite improved by approximately 76.66%, a vital characteristic for applications facing abrasive conditions. The corrosion testing demonstrated an 8.33% enhancement in corrosion resistance with the Ti/5% YSZ/2% Cu composite.

Enhanced Mechanical Properties of Cast Cu-10 wt%Fe Alloy via Single-Pass Friction Stir Processing

In this study, Cu-10 wt% Fe alloy in as-cast state was modified using friction stir processing (FSP). The microstructure evolution of Cu-10 wt% Fe alloys in different states was characterized in detail using scanning electron microscopy (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The results show that due to dynamic recrystallization, the FSPed Cu-10 wt% Fe alloy obtained a uniformly equiaxed ultrafine microstructure with low density of dislocation, high proportion of high-angle grain boundaries (HAGBs), and high degree of recrystallization. Fine equiaxed grains with an average size of 0.6 μm were produced after FSP. Many fine-precipitate Fe-phases with an average size of 20 nm were uniformly distributed in the Cu matrix. The FSPed samples possessed excellent mechanical properties, such as high Vickers hardness (163.5 HV), ultimate tensile strength (538.5 MPa), and good elongation (16%). This single-pass FSP method does not require subsequent aging treatment and provides a simple and efficient way to improve the properties of Cu-Fe alloys.

An insight on optimization of FSP process parameters for the preparation of AA5083/(SiC-Gr) hybrid surface composites using the response surface methodology

Aluminum alloys are known for their extensive use in aerospace, automobile, marine, etc., industries due to their excellent inherent properties. Recent studies have developed different methods to modify the surface properties of aluminum by producing surface composites, such as the friction stir processing (FSP) method. The current study made an effort to develop a new hybrid surface composite of AA5083/(SiC-Gr) using the FSP method. For FSP process optimization, the response surface methodology (RSM) has been used. For creating the mathematical model using RSM, various input process parameters of the FSP are selected to predict the output characteristics of the prepared hybrid composite. A Box–Behnken design was used for the process with four factors, each factor was used with three levels, and the RSM was utilized to form a regression model to predict the responses. The ANOVA analysis suggests that NoP (number of passes): 3 and RV (reinforcement volume): 75:25 (SiC: Gr) ratio are the significant parameters of the study with a p-value less than .05. The novelty of this study lies in the development of a new hybrid surface composite of AA5083/(SiC-Gr) using the friction stir processing (FSP) method, with optimization achieved through the response surface methodology (RSM) and multi-objective selection criteria, resulting in predicted outcomes within a range of ±10% of the experimental observations.

Advancement in Engineering Integral Pathways for Manufactured Structures

Abstract A new friction stir processing method, submerged bobbin tool tunneling, creates subsurface integral pathways in components that can be used as channels for wiring, gases, fluids, powders, or as a lightweighting technique.

Effect of nano-TiO2 particles addition on dissimilar AA2024 and AA2014 based composite developed by friction stir process technique

Aluminum composite materials have gained immense popularity in the construction and aerospace industries as these materials are lightweight, durable, and exhibit a high strength-to-weight ratio. The present study aims to develop dissimilar AA2024 and AA2014-based composite materials using nano-TiO2 reinforcement particles via Friction Stir Processing (FSP) techniques. The FSP technique is a solid-state processing method that is used to modify the properties of metal alloys without altering their chemical composition. The samples were prepared by placing a nano-TiO2over AA2024 and AA2014 aluminum alloys sheet and subjected to FSP process parameters. The microstructure, hardness, and tensile properties of the composite samples were assessed using scanning electron microscopy (SEM), Vickers hardness tester, and tensile testing machine respectively. The results showed that the FSP technique led to the formation of a homogeneous and fine-grained microstructure in the composite samples. The nano-TiO2 reinforcement also provided additional strengthening to the AA2024 and AA2014 aluminum alloys matrix resulting in improved hardness and tensile properties of the composites. The resulting composites exhibited enhanced wear resistance properties. The FSP method presented in this study has implications for extending the properties of other metal alloys, opening up new avenues for research in the field of materials science.

Improving the wear resistance and mechanical properties of hybridized AZ80 Mg/CeO2+ZrO2 surface composite by friction stir processing: Effect of pin geometry

Geometrically modified pins were utilized for the development of the hybrid AZ80 Mg/CeO2+ZrO2 composite by using the friction stir processing method. The local shear punching strength, structure, hardness, and wear of the hybrid AZ80 Mg/CeO2+ZrO2 composite were investigated. A change of the tool profile from cylindrical to conical pin profile eliminates particle clusters and inherent voids while the nugget shape, vortex width, and surface flash are also affected due to the tool's volumetric difference. Microstructural changes (grain and particle sizes) are also positively improved by the tapered pin tool, and these have about 24% improvement on the local shear strength of the composite while the hardness and the wear performances of the composite are also improved.

Microstructural and sensor data analysis of friction stir processing in fabricating Al6061 surface composites

Aluminium alloys, having high strength, ductility, and toughness, are useful structural materials. Composites of these with ceramic reinforcements improve the hardness and wear-resistance, making them suitable for use in the aerospace and automobile industries. Since surface properties play a crucial role for most applications, the manufacturing of surface composites of aluminum alloys is recommended. For this purpose, friction stir processing (FSP) is being utilized nowadays. It refines the microstructure with a homogeneous dispersion of reinforcements into the matrix and improves physical characteristics like surface hardness, wear resistance, strength, etc, while retaining the original characteristics of remaining volume. The study aims to investigate and compare the temperature and vibration sensor data while manufacturing Al6061 surface hybrid composites by using FSP tools with different geometries. The FSP method is utilised for the fabrication of the composites with the copper and graphite powders mixture (1:1), reinforced into the matrix surface by using two H13 tools with two different pin profiles - threaded cylindrical and plain cylindrical. Holes of different diameters and depths are drilled on the Al6061 matrix for reinforcement addition. This FSP process is investigated using a thermal gun and a Cross-Domain Development kit for temperature and vibration measurement. The variation in the vibration signals occurring on the composite workpiece during the entire process with the temperature measurements at equal intervals, is obtained. It is found that both the temperature and vibration amplitudes (400 °C and 1111Hz) are lower in the composites fabricated by FSP tool with threaded pin profile than that by FSP tool with plain pin profile (455 °C and 1305 Hz). Also, the processed samples are investigated for the microstructure by Field Emission Scanning Electron Microscope and Energy-Dispersive x-ray Spectroscopy tests. It is found that the reinforcements are dispersed more uniformly and much reduced in size (0.5482 μm) when prepared by the FSP tool with threaded cylindrical pin, while these particles are heterogeneously dispersed and less reduced in size (1.11 μm) when processes by the FSP tool with plain cylindrical pin. This research can be used to further monitor and control properties like temperature, vibration, force, current, etc, to obtain a uniform reinforcement dispersion with improved mechanical properties during the surface composite preparation by FSP.

Effect of the processing route on the microstructure and mechanical behavior of superlight Mg-9Li-1Zn alloy via friction stir processing

In this study, the effect of the processing route using a friction stir processing (FSP) method on the microstructure and mechanical behavior of a Mg-9Li-1 Zn alloy was systematically investigated. In the FSP method, the odd-numbered (1st and 3rd) process directions and even-numbered (2nd and 4th) passes were alternated to distribute the strain throughout the whole processed zone uniformly. Consequently, the processed zone had a much more uniform microstructure and hardness distribution than the processed zone obtained using the conventional FSP method. Using this method, the grain size of a Mg-9Li-1 Zn sheet alloy was refined from ∼31 μm to ∼0.21 μm with uniformly distributed α and β phases. The processed alloy exhibited a high strength-ductility synergy with an ultimate tensile strength (UTS) of 220.1 MPa and total elongation of 70.0% at a strain rate of 10 −3 s − 1 , overwhelmingly higher than those of the base metal, 155.6 MPa in UTS and 36.0% in elongation. The in-situ SEM-DIC analysis and TEM observation demonstrated that such an outstanding ductility with moderate strength is caused by grain boundary sliding, the dominant deformation mechanism of the ultra-fine-grained sample after FSP. The processing route with reverse processing direction was proven to be efficient in producing the ultrafine grain size microstructure and improving the mechanical properties of superlight Mg-9Li-1 Zn alloy.

Review and analysis of the effect of variables on aluminium based surface composite fabricated through friction stir processing method

Review and analysis of the effect of variables on aluminium based surface composite fabricated through friction stir processing method

Influence of Friction Stir Process on the Physical, Microstructural, Corrosive, and Electrical Properties of an Al-Mg Alloy Modified with Ti-B Additives.

In this study, two successive methods were used to improve the grain structure and the mechanical and physical properties of Al 5052 aluminum alloy. The modifying elements, 0.99 wt.% of titanium (Ti) and 0.2 wt.% of boron (B), were added during the casting process. After solidification, single- and double-pass friction stir processing (FSP) were performed to achieve additional grain refinement and disperse the newly formed phases well. The addition of Ti–B modifiers significantly improved the mechanical and physical properties of the Al 5052 aluminum alloy. Nevertheless, only a 3% improvement in microhardness was achieved. The ultimate strength (US), yield strength (YS), and elastic modulus were investigated. In addition, the electrical conductivity was reduced by 56% compared to the base alloys. The effects of grain refinement on thermal expansion and corrosion rate were studied; the modified alloy with Ti–B in the as-cast state showed lower dimension stability than the samples treated with the FSP method. The grain refinement significantly affected the corrosion resistance; for example, single and double FSP passes reduced the corrosion rate by 11.4 times and 19.2 times, respectively. The successive FSP passes, resulting in a non-porous structure, increased the bulk density and formed precipitates with high bulk density.

Wear Analysis of copper based surface composites prepared by friction stir processing

Copper based surface composites are widely getting importance in various applications because of their decent mechanical, tribological and thermal properties. In the present experimental work, an attempt was made to prepare the surface composites with copper material as substrate using friction stir processing method. Three specimens were prepared by adding aluminium oxide, boron carbide and the mixture of both particles to the surface of the copper and stirred using a square pin profiled tool. The various process parameters of the friction stir process were maintained constant. The wear behaviour of the specimen such as wear rate, coefficient of friction, and friction force was studied using Pin on disc method. The test results revealed that hybrid surface composites had better wear resistance due to/ the low coefficient of friction and friction force followed by boron carbide and aluminium oxide particles mixed surface composites. The friction force was 20 times higher than the friction coefficient and this factor remains constant for the entire test run.

Optimization of wear characteristics on boron carbide/flyash reinforced aluminum alloy (7000 series) hybrid composites

In this research process, AA7475 was represented as a main material, boron carbide(B4C) along with flyash (FA) are utilized for reinforcements or additional elements to improve the wear behavior by using friction stir processing method(FSP).Al hybrid composites are made by FSP by change the level of the altered processing parameters such as Tool rotation speed TR (800,1000 & 1200 rpm), Tool travel speed TT (30, 40 &50 mm/min), groove width GW (1,1.5 & 2 mm) and % of reinforcements RS (B4C −5,7.5,10 wt% & fixed FA 5%). wear experimentations were conducted on POD apparatus. Taguchi orthogonal array (L9) have been selected for doing optimization process in which Signal to noise ratio (SN Ratio) helped to identify highest wear amount among the prepared samples.

Influence of reinforcing particles on microstructure and mechanical properties of friction stir processed aluminium alloy AA7075‐T651

AbstractThis paper emphasis the improvement of mechanical properties of AA7075‐T651 using friction stir processing through localized surface modification by adding nano boron carbide particles. The reinforcement techniques such as the groove and blind hole methods were used by changing reinforcements of nano boron carbide and a matrix of AA7075‐T651 surface composites volume percentages (2 %, 4 %, and 6 %) along with tool rotational speed and processing speeds. Optical microscopy, scanning electron microscope and x‐ray diffraction analysis were used to examine the particle dispersion for the surface composites and to correlate with the enhanced mechanical properties. Results revealed that high input parameters have given grain coarsening and precipitate agglomeration and low input parameters provide poor nugget metal consolidation and no vertical material flow. The L9 orthogonal Array designed and optimized the process parameters for enhancing the surface properties of processed samples. Mechanical properties like ultimate tensile strength, yield strength, hardness, percentage of elongation and impact strength were evaluated for the groove friction stir processing method and blind‐hole friction stir processing methods. From the results, it has been observed that the blind‐hole technique resulted in higher hardness and the homogenous dispersion of nano boron carbide particles in the stir zone than the groove method. Consequently, for blind‐hole friction stir processing, grey relational analysis (GRA) and particle swarm optimization (PSO) approaches were proposed to optimise process parameters. From the compared optimization results between grey relational analysis and particle swarm optimization, particle swarm optimization approach was shown the best optimization results. Successively, the optimum condition in the respective experimentation is accomplished. Based on these observation and results, final validation tests were carried by changing the volume percentages of reinforcement keeping tool rotation speed and tool processing speed as constant. It is apparent that dynamic recrystallization in aluminium alloy at the processed zone due to presence of heterogeneous nucleation sites with nano boron carbide particles.

Friction stir processing of boron carbide reinforced aluminium surface (Al-B4C) composite: Mechanical characteristics analysis

In this article, the boron carbide reinforced Aluminium alloy surface composite material was fabricated through the friction-stir processing method. The Al6061 alloy and B4C particles were used as matrix and reinforced materials respectively. The influences of volume percentage of boron-carbide, traveling feed rate, and rotational speed on tensile strength and wear were investigated using the L9 Taguchi technique. The moderate rotating speed and traveling speed of the tool have been preferred to attain optimum responses. The highest tensile strength of 347 MPa and minimum wear of 55 µm were obtained from 15% of the volume of boron carbide particles, 1400 rpm of rotating speed, and 40 mm/min traveling speed of the tool. The optimum Al6061-B4C surface composites micro-structure has also been studied through scanning electron microscope images.

Microstructure evolution and mechanical properties of TiC/Ti6Al4V medical composite processed by severe plastic deformation

Gradient materials can achieve both external strengthening and internal toughening, which has great potential to break the strong plastic tradeoff. Titanium carbide (TiC) particle is conducive to form a wearable surface in biomedical Titanium (Ti) alloy. In this work, gradient TiC/Ti6Al4V composites were successfully prepared by friction stir processing (FSP). Microstructure, texture and mechanical properties of the material were systematically characterized. Scanning electron microscopy (SEM) showed that the equiaxed grains near the machined surface were transformed into elongated grains inside. The results of energy spectrum analysis (EDS) showed that there was element aggregation near TiC particles. X-ray diffraction (XRD) indicated martensitic transformation in the stir zone and in the transition zone. The results of nano indentation showed that the hardness of stir zone was higher. In order to promote recrystallization and improve the hardness of the transition zone, high temperature rapid heat treatment was carried out after FSP. When the sample was heated at 700 °C and cooled in the furnace, the hardness increased to the maximum. In the process of rapid heating, the dissolution of elements near TiC particles also led to the increase of hardness. This study provides a new idea for surface modification of gradient titanium alloy by using FSP method to improve its mechanical properties.

Comparison of cavitation erosion behaviors between the as-cast and friction stir processed Ni–Al bronze in distilled water and artificial seawater

Abstract In this investigation, the friction stir processing (FSP) method was utilized to improve the properties of the surface of the as-cast nickel aluminum bronze (NAB) alloy in two different processing parameters. The microstructure, element distribution and mechanical properties of the alloys before and after FSP were observed and estimated. The cavitation erosion behaviors of the original NAB and FSP NAB in different test solutions were also discussed. The results indicated that the microstructure became finer and more homogeneous and the element distribution became more uniform after FSP. The FSP NAB alloys also possessed better mechanical properties. The lower cumulative cavitation erosion mass loss of FSP NAB in all test solutions indicated the fact that the cavitation erosion resistance of the as-cast NAB could also be improved by the FSP method. Compared to the as-cast NAB, the corrosion effect on the cavitation erosion was more significant for the FSP NAB alloys owing to their better pure cavitation erosion resistance.

Wear and Mechanical Behaviour of Magnesium AZ31 alloy Reinforced with MoS2 through Friction Stir Processing for Aerospace Applications

Friction Stir Processing (FSP), a solid-state processing technique employed to modify the microstructure, is based on the principles of friction stir welding. FSP is one of the most promising techniques for the production of surface composites. In this investigation, AZ31 magnesium alloy is reinforced with molybdenum disulfide (MoS2) through a friction stir processing method. Before and after the fabrication of the surface composites the wear tests were conducted by varying the condition of sliding load (25 N & 35 N), sliding distance (1 km & 2 km), and sliding velocity (1 m/s & 2 m/s). Hardness values were measured by using the Brinell hardness tester. Both hardness and wear tests were conducted as per the ASTM standards. After reinforcement, composite material enhances hardness values. The wear rate also reduces as MoS2 acts as a solid lubricant material.

Fabrication of hybrid (AA6061/SiCp/B4C) composites using FSP method and analysing the thermal behaviour in the weld region

The aim of this effort is to use friction stir processing to make an aluminium-based hybrid composite (FSP). Because of their high strength-to-weight ratio, aluminium alloys are widely used in the nautical, concrete, transportation, and aircraft industries. Friction strengthened metal matrix composites (PRMMC) is made from A6061 and its reinforcements B4C and SiCp particles. particles strengthened metal matrix composites (PRMMC) was produced by friction stir processing (FSP). The optical microscopy, hardness tests used to characterize the samples. The results indicated that the uniform distribution of SiCp/B4C elements in A6061 matrix by FSP process and heat treated this can be advance the mechanical possessions of samples. Therefore, pretending the mechanical performance of a prepared new specimen is very important to assess the protection of the plate.

Investigation on surface modified Al7075 with niobium by friction stir processing

In this present work Aluminum alloy 7075 is used as a base metal and niobium is used as an additive material to enhance the surface microstructure and mechanical properties like tensile strength, hardness and wear by using friction stir processing method. For optimizing the process parameters Taguchi L9 orthogonal array has been used. The process parameters for the present work are rotational speed, transverse speed and groove width. The experimental results indicate that rotational speed of 900 rpm, transverse speed of 20 mm/min and groove width of 1.2 mm gives maximum tensile strength of 344.79 MPa, hardness value of 283 and wear of 1.290 mm3. The microstructure and mechanical properties such as tensile strength, hardness and wear has been enhanced by addition of niobium in the Al7075 metal. The optimum process parameter from signal-to-noise ratio is used to identify the maximum tensile strength, hardness and wear behaviour. The optimized values are rotational speed of 700 rpm, transverse speed of 40 mm/ min and groove width of 0.6 mm are obtained from signal-to-noise ratio.