FSP Process Research Articles

Optimization of friction stir process parameters for enhanced mechanical properties in surface-alloyed ZK60 magnesium with Tin (Sn): an RSM-ANN hybrid approach

ABSTRACT In the present work, the surface of the ZK60 Mg alloy was alloyed with tin (Sn), and the FSP process parameters have been optimized for the better mechanical properties by employing response surface methodology (RSM). Furthermore, RSM was combined with artificial neural networks (ANNs) to evaluate and compare the predictive capacity of both the models. FSP process parameters, namely, tool rotational speed (S), feed rate (F), number of passes (N), and weight percentage of Sn (W) were selected as influential parameters for optimization. The optimum conditions that were predicted by the RSM model to maximize the ultimate tensile strength (UTS) and % elongation (%EL) were a tool rotational speed of 2000 rpm, a feed rate of 0.39 mm/sec, 3 number of passes, and 8 wt.% of Sn which yields the maximum tensile strength of 217 MPa and the maximum %El of 26%.

Fabrication of graphite-reinforced 6201Al matrix composite with simultaneous enhancement of mechanical and electrical properties by multi-pass friction stir processing

In this study, graphite-reinforced 6201 aluminum alloy matrix composites were fabricated by multi-pass friction stir processing. The mechanical properties and electrical conductivity of the composites were tested, the microstructure and composition of the composites were analyzed by scanning electron microscope and Raman spectroscopy. The results showed that the graphite-reinforced 6201Al matrix composite achieved simultaneous improvement of mechanical and electrical properties compared to the base material, with a 19.5 % increase in ultimate tensile strength and a 1.2 % increase in electrical conductivity. Microstructural and compositional analysis revealed that the graphite reinforcement in the composites was significantly fragmented during FSP, and its size decreased while the number of atomic layers reduced with increase in FSP passes. A directly bonded Al-C interface is observed between the graphite reinforcement and the matrix, and no interface products such as Al4C3 were generated. The graphite reinforcement in the matrix simultaneously serves as a hindrance to dislocation motion and the expansion of microvoids during the tensile process, thereby leading to an enhancement in the tensile strength of the composite. The improvement in the electrical conductivity of the composite is attributed to two factors. On one hand, the structure and properties of graphite-reinforced phase is transformed to be closer to graphene after the severe plastic deformation during FSP process. On the other hand, the directly bonded Al-C interface between the matrix and the reinforcement is able to transfer electrons across the interface.

The effect of friction stir processing on the hydrogen susceptibility of AA5083 specimens after hydrogen cathodic charging

The present study investigated the effect of hydrogen on the mechanical degradation of friction stir processed (FSPed) 5083 aluminum alloy by intense hydrogen cathodic charging (HCC). The effect of different numbers of FSP passes was investigated: 3 and 8 passes, respectively. Hydrogen-charged and uncharged specimens were subjected to tensile testing and microhardness evaluation analysis, and were examined through optical microscopy, focus variation microscopy (FVM), and scanning electron microscopy (SEM) both on the microstructure and fracture zone. The results showed that the FSP process introduced a refined microstructure with finer grains. This led to an improved mechanical response during tension tests of the uncharged specimens; the energy absorption increased from 85 MJ/m3 of the base material to 94 MJ/m3 and 97 MJ/m3 for the 3 and 8 FSP passes, respectively. The introduction of hydrogen through the HCC process led to a more brittle mechanical response with a decrease in the energy absorption capability for all the charged specimens. The more prone specimen was the 8 FSP passes specimen where the energy absorption dropped by 20% and 71% for the two different charging current densities. The 3 FSP passes specimen presented a reduction of energy absorption of 4% and 18%, respectively, where the base material presented a reduction of 8% and 14%, respectively. This brittle response is also evident from the microhardness testing where the hydrogen charging led to increased surface hardness values. The 3 FSP passes specimen presented a better mechanical response with respect to the base material specimen (and the 8 FSP passes specimen) for all the charging conditions, and this led to the conclusion that a small number FSP surface modification could be a beneficial surface modification process as it improves the mechanical response of the material and is not significantly affected by hydrogen charging environments.

Highly Crystalline Nanosized NaTaO3/NiO Heterojunctions Engineered by Double-Nozzle Flame Spray Pyrolysis for Solar-to-H2 Conversion: Toward Industrial-Scale Synthesis

Sodium tantalate, NaTaO3, nanomaterials are highly potent photocatalysts for hydrogen production from H2O. Proper interfacing of nano-NaTaO3 with finely dispersed nano-NiO can produce an n–p type-II heterojunction {NaTaO3/NiO} with superior photocatalytic conversion efficiency. Making such nanomaterials widely applicable requires the establishment of an industrial-scale synthesis method, which would allow at least control of nanosize, composition, crystallinity, and interface. Herein, we have developed a scalable double-nozzle flame spray pyrolysis (DN-FSP) method, for one-step synthesis of highly crystalline {NaTaO3/NiO} heterojunctions, with specific emphasis on the NaTaO3 nanosize and interfacing with ultrafine NiO nanoparticles. The FSP process allows the single-step synthesis of very small NaTaO3 (<15 nm), with ultrafine NiO (<3 nm) finely dispersed on NaTaO3. Utilizing the versatility of FSP, we analyze the thermodynamics of nanosized NaTaO3 perovskite gas-phase formation in flames. A library of large/small nano-NaTaO3 and Ta2O5 was synthesized, employing different NiO deposition methods. The double-nozzle FSP-made {12 nm NaTaO3/NiO} achieved benchmark photocatalytic H2 production >10.000 μmol g–1 h–1 from a H2O/methanol mixture, without implementation of any noble metal as a cocatalyst. This corresponds to a solar-to-hydrogen (STH) conversion efficiency of 0.89%, which is well above the average. The photocatalytic mechanism underlying this performance is discussed based on in situ monitoring of the photoinduced holes and electrons using electron paramagnetic resonance spectroscopy. Specifically, the carrier kinetics indicates that the superior STH conversion achieved by {NaTaO3/NiO} is inherently related to the small NaTaO3 nanosize that allows critical migration of photoinduced electron/hole pairs to the particle surface, outcompeting recombination.

Microstructure and properties of FeCoNiCrAl high-entropy alloy particle-reinforced Cu-matrix composites prepared via FSP

Although copper has excellent thermal conductivity, poor wear resistance seriously limits its development. In this paper, a Cu matrix surface composite material reinforced by FeCoNiCrAl high-entropy alloy particles was prepared by friction stir processing. The microstructure and properties of the composite were investigated. The results showed that both the FSP process and the addition of HEA particles contributed to the refinement of the Cu-matrix grains. A diffusion layer with a width of about 0.8 µm was formed at the interface between the HEA particles and the Cu matrix. Compared with received Cu, the microhardness of Cu matrix in the composites was increased by 69.8%, the wear rate was reduced by 29.7%, and the wear resistance was significantly improved. Mean while, the ductility of the composite was consistent with that of the received Cu, and the thermal conductivity reached 87% of the received Cu. Therefore, this paper provided a new possibility for developing multifunctional structural materials with high wear resistance, high ductility, and high thermal conductivity.

Effect of nanoparticles and multipass friction stir processing on microstructure and mechanical properties of AA7475

The base metal, AA7475, initially contained nanoparticles of SiC within a coarse dendritic structure. The multipass FSP (MPFSP) process successfully broke these coarse and dendritic clusters, resulting in a homogenous microstructure in the stir zone. This inhibition led to a continual reduction in grain size. The presence of SiC reinforcement particles also played a role in imbvproving the microstructure and tensile properties of the MPFSP/SiC composite. The optimal process parameters for MPFSP/SiC on AA7475 were identified as a rotational tool speed of 1500 rpm, welding speed of 40 mm/min, and a tilt angle of 2°. As the number of FSP passes increased, the agglomeration of SiC particles reduced, further enhancing the dispersion. Before MPFSP/SiC, the base metal AA7475 exhibited a tensile strength of 410±5 MPa and a % strain of 10.83±0.3. However, after MPFSP/SiC, the tensile strength increased with the number of FSP passes. The highest tensile strength of 521±8 MPa was observed after the 5 th pass of FSP. This increase in tensile strength was attributed to the presence of fine grains formed through the DRX mechanism during the MPFSP process.

Industrial Scale Engineering of Photocatalytic Nanomaterials by Flame Spray Pyrolysis (F.S.P.)

Flame Spray Pyrolysis is an attractive technology for the synthesis of nanosized materials with distinct characteristics. Industry leaders such as Cabot, Cristal, DuPont, Evonik, and Ishihara manufacture flame-made materials in millions of tons per year including carbon blacks. Herein we exemplify the application of large-scale FSP process for the synthesis of highly active photocatalysts, able to achieve high H2, O2 production yields from H2O. Precise control of W-doping along with controlled Scheelite-phase BiVO4 is a benchmark oxygen-evolving nanocatalyst. Double-Nozzle FSP is demonstrated to allow the production of highly efficient {noble metal} TiO2 heterostructures. Key-Performance-Indicators that allow transition of Lab-Scale to Industrial-Scale engineering of semiconductors are discussed, including cost-analysis and environmental impact of the production process.

Experimental Investigation of Peak Temperature and Microhardness in Friction Stir Processing of AA6082 T6 using Taguchi GRA

Friction stir processing demonstrated tremendous potential for improving mechanical properties and its success relies on the optimal level of process parameters that result in a flawless stir zone. The present study is an experimental investigation of performance characteristics peak temperature and microhardness on FSPed AA6082-T6. The experiments are designed using the Taguchi L16 orthogonal array by considering four different levels of rotational speed, traverse speed, shoulder diameter, and tilt angle. The grey relational analysis is used for multiple responses to optimise the FSP process parameters and analysis of variance is utilised to establish the relevance of parameters for these responses. According to the findings, the shoulder diameter and traverse speed are the most important determinants for peak temperature and microhardness. It is observed from the experimental analysis that the main reasons for defect formation are either excessive or inadequate heat generation. The multi-response optimal condition is attained at a rotating speed of 1400 rpm, transverse speed of 112 mm/min, shoulder diameter of 25 mm, and tilt angle of 1º.

Microstructural, mechanical and wear behavior of A7075 surface composite reinforced with WC nanoparticle through friction stir processing

The effect of FSP process parameters such as mechanical, microstructural and wear behaviour on A7075/WC surface composites was examined. In the present investigation, 15 wt% WC was used as a reinforcement for producing FSP surface composite through cylindrical tapered tungsten carbide pin tool. It was observed that WC reinforced FSPed surface matrix under traverse speed of 60 mm/min with 1200 rpm rotational speed reduced the matrix particle’s size and distributed homogeneously throughout the surface. Also, as the FSP passes increases the broadening and offsetting of the diffraction peaks of WC and A7075 was observed. At same process parameters corresponding to 6- passes, the micro hardness as well as tensile strength were increased up to 35% and 52%, respectively, compared to base material (A7075). In addition, the increase in FSP passes increases both slurry erosive wear resistance and abrasive wear resistance due to repeated self-heat treatment phenomena.

Effect of Zirconium Dibromide and Aluminum Oxide Hybrid Particle Reinforcement on the Mechanical, Microstructure and Wear Properties of AA6063 Surface Metal Matrix Composite

In the present study Aluminum 6063 as the matrix and with Zirconium dibromide and Aluminum oxide as the reinforcement particle Metal Matrix surface composites were fabricated by friction stir processing. By the addition of reinforcements such as Zirconium Dibromide and Aluminum Oxide used as the strengthening agents during FSP process certainly made the MMC more wear resistant and harder than the base matrix. The effect of varying reinforcement percentage on the Mechanical wear and microstructure properties were studied. The Micro hardness showed an increasing trend in the nugget zone. The wear rate decrease with increase in volume percentage of hybrid reinforcement. FESEM images of the samples displayed uniform distribution of the particle in the matrix. And also reiterated the formation of hybrid particles.

Extraction of Cr from CCLW and its utilisation in the development of composite by friction stir process

ABSTRACT Chrome containing leather waste (CCLW) produces lots of air and soil pollution. CCLW is produced from leather industries. CCLW is very harmful to the human health after rotting. However, by using this waste at right time and right place, the pollution generated by them can be prevented. Though various attempts have been made to utilise CCLW in various applications, some attempts were also observed in the development of bio-composite material. But, still no researchers used CCLW in the development of aluminium-based composite material as reinforcement by FSP technique. This study attempts to use CCLW as reinforcement after the extraction of Cr in the form of collagen powder. Ball-milling of collagen powder and alumina has been carried out for 100 h. Mixture of ball-milled reinforcement particles were used to develop aluminium-based composite material. FSP technique was used to develop surface composite. FSP process parameters were first optimised using Box-Behnken Design. Optimum PSP parameters were found to be the number of tool pass of 1, tool rotational speed of 943.12 RPM and transverse speed of 23.56 mm/min. Tensile strength and hardness of composite developed at optimum FSP parameters improved by about 17.95% and 32.44%, respectively, with respect to the base material.

Development of Mg-based biodegradable composite using friction stir processing for orthopedic application

The latest research shows the construction of a biodegradable composite based on magnesium (Mg-Zn-Mn) by means of friction mixing. The Zn and Mn micro powder parts were enhanced to increase corrosion resistance and mechanical properties on a surface dependent on Mg-alloy. The microstructure and mechanical properties have been studied for their influence on various forms of FSP process parameters: tool-geometry (Tg), movement speed (TS) and rotations speed (Rs). The analysis of the Mg-based composite as formed has been investigated with microstructure, elemental and phase composition. The Vickers' micro-hardness tester and universal testing machine calculated the micro-hardness and tensile strength of the as formed Mg-based composite (UTM, BIS). The microstructural test showed that a Mg-base composite with a coarse grain size range of approximately 25 μm was also distributed with the reinformed material in the matrix. The mechanical properties are tensile resistance (UTS) of 125 MPa with an elongation percentage of 13.47 percent and are smaller than the young 35 MPa modulus near the cortical bone of the cortical bone.

Artificial intelligent approach for process parameters modeling of friction stir processing

In the current study, an ANFIS model has been created using FSP process boundaries to predict the UTS & Hardness of Al-Y 2 O 3 composite. This work involved modelling, experiment, and optimization of FSP process parameters. For optimization and prediction process has been finished by four input variables such as: traverse speed, spindle rotary speed, no of passes and tool rotation direction. Total 36 experiments were carried to determine the UTS and hardness with different input parameters combination and all data sets that is 216 rules sets were applied to prediction, testing, and optimization of mentioned UTS & hardness by the help of Adaptive Neuro Fuzzy Inference (ANFIS). The results showed that the traverse speed had been 90 mm/min, the spindle rotating speed seemed to be 970 RPM, the multi-no-passes and the CCLW spindle rotation direction given the maximum hardness and UTS. Afterwards one confirmation test was executed to verify the ANFIS optimization solution.

Soft computing model for predicting the wear resistance of friction stir processed aluminum alloy AA5083

In this study, AA5083 plates were friction stir processed to improve the hardness by refining the grains and dispersing the β phase in the matrix. Tool rotation speed, tool traverse speed, and tool shoulder diameter were varied as per the face-centered central composite design and FSP trials were performed. The wear resistance of the friction stir processed specimens was estimated by conducting a wear test using a pin-on-disc tribometer. It was observed that the wear resistance was higher than the base specimens and TRS, TTS and SD had a significant effect on the wear resistance. An artificial neural network model and a fuzzy logic model were developed to predict the wear resistance of the friction stir processed specimens. As the Sugeno Fuzzy model had greater prediction efficiency than the ANN model, it was used to study the effect of FSP process parameters on the wear resistance of the specimens. The results indicate that a TRS of 1000 rpm, TTS of 30 mm/min, and SD of 18 mm maximized the wear resistance of the processed plate to 8820 N-m/kg.

Effect of FSP process parameters with air blowing on microstructure and hardness of NiAl Bronze alloy

The present work investigates the effect of friction stir processing on microstructure evolution—grain refining and phase transformation- and hardness of NiAl bronze alloy. NiAl bronze alloys have a wide range of industrial applications especially in the marine field. The technique is based on applying friction using a rotating tool causing heat generation and material mixing. The effect of process parameters, such as; rotation speed, traverse speed, forced convection were investigated in this research. At constant traverse speed, the effect or rotation speed was studied at 800, 1000, and 1200 rpm. At constant rotation speed, the effect of traverse speed was studied at 40, 64, and 93 mm min−1. Minimum grain size was achieved at FSP conditions 800 rpm/93 mm min−1. Highest average hardness value was achieved by FSP 1200/93. At constant rotation and traverse speeds, the application of forced convection using air blowing at a rate of 4.5 m3 min−1 was studied and it was found to reduce the grain size within the SZ and to increase the average hardness value.

Review of Friction Stir Processing of Aluminium Alloys

An advancement to the principles of friction stir welding is the friction stir processing, a technique for modifying the surface, which involves the modification of the local microstructure by refining the microstructure and through localized plastic deformation of the specimen material. The tool that is involved in the process consists of a rotating tool which has a shoulder and pin inserted into the single piece of material. The area which needs to be examined with this process is traversed by this tool in a desired direction. When the shoulder of the tool and the workpiece comes into contact with each other, with the tool traversing at a particular travelling speed and an optimal rotational speed, friction is developed between the two surfaces. This in turn increases the heat of the material to a limit where the material undergoes plastic deformation. Hence when such an exposure occurs localized plastic deformation and the thermal property increase leads to a drastic change in the local microstructure. Various properties have been examined when the material undergoes friction stir processing which involves the production of nanograin, the surface hardness increases followed by the the fatigue strength, wear property and tensile strength of the material. This review paper focuses mainly on the change in microstructure and mechanical properties of Aluminium alloys and their composites and the effect of FSP process through the study of the current trend and the development of FSP to various parameters.

A Review Study of Friction Stir Processing of Aluminum Alloys

Friction stir processing is a Nobel technique established for its capacity to alter the microstructures and properties of a metal to its enhanced one with the assistance of extreme and confined plastic distortion. On the off chance that in tests, with effectively cooled magnesium-amalgam work pieces the micro hardness gets tripled in the region of the rubbing mix handled crease i.e. 120-130 Vickers hardness. In FSP process a more homogenous and refined microstructure of material is obtained. Repaired regions from FSP process are prevalent in quality and furthermore have better formability looked at than parent material. E.g. aluminum castings can be prepared to tie voids, or expulsions can likewise be enhanced in much focused on zones. FSP in blend with superplastic framing gives the possibility to shape complicated-molded parts at high strain rates and in segment thicknesses which isn’t conceivable utilizing customary superplastic handling. In this article of survey, current phase of FSP and improvement jumped out at comprehend it is tended to.

Analysing the influence of FSP process parameters on IGC susceptibility of AA5083 using Sugeno – Fuzzy model

Aluminium alloy AA5083 was friction stir processed to improve the intergranular corrosion (IGC) resistance. FSP trials were performed by varying the process parameters as per Taguchi’s L18 orthogonal array. IGC resistance of the friction stir processed specimens were found by immersing them in concentrated nitric acid and measuring the mass loss per unit area. Results indicate that dispersion and partial dissolution of secondary phase increased IGC resistance of the friction stir processed specimens. A Sugeno fuzzy model was developed to study the effect of FSP process parameters on the IGC susceptibility of friction stir processed specimens. Tool Rotation Speed, Tool Traverse Speed and Shoulder Diameter have a significant effect on the IGC susceptibility of the friction stir processed specimens.

Effect of doping and crystallite size on the electrochemical performance of Li4Ti5O12

Defect spinel phase lithium titanate (Li4Ti5O12) has been suggested as a promising negative electrode material for next generation lithium ion batteries. Flame spray pyrolysis has been shown to be a viable fast, one-step process for synthesis of nanoparticulate Li4Ti5O12. However, due to the rapid quenching that is integral to the process the crystallite size remain very small and non-uniform.To overcome this shortcoming a vertical flow tube furnace was used to increase the high-temperature residence time. This resulted in an increase in the crystallite size and crystallinity of the product. As a result of this increase the electrochemical performance of the Li4Ti5O12 was markedly improved.Furthermore, silver doping of the Li4Ti5O12 material can be carried out simultaneously with its synthesis in the FSP process. The resulting nanosized silver particles on the surface of the Li4Ti5O12 particles further improve the electrochemical performance during high current operations.The specific capacities of these high-temperature synthesised pure and silver-doped Li4Ti5O12 nanoparticles were found to increase by up to 6% and 19%, respectively, compared to a commercial reference. Thus the technique provides a simple method for synthesising superior quality Li4Ti5O12 for battery applications.

Cast aluminium matrix composites modified with using FSP process – Changing of the structure and mechanical properties

The aim of this study was to explain the influence of the plastic deformation generated in friction stir processing on the changing concentration and distribution of SiC reinforcement particles in the cast composite A339/SiC/p, as well as determine its mechanical properties. Aluminum matrix reinforced with 10% vol. SiC particles was modified using friction stir processing method. Changing of distribution of the reinforcement particles was calculated and analysed using new mathematical RVE theory with Mityushev–Eisenstein–Rayleigh sums (M-sum) and PointSel software. The mechanical properties were determined on the basis of compression and hardness tests.The significant changes in the concentration and distribution of SiC particles were observed. Mechanical testing of selected deformed areas showed significant differences in the values of the plastic flow stress and hardness in thermomechanical hardening areas, approximately from about 30–40%.