Strong Joints Research Articles

Effect of Preheating Parameters on Extrusion Welding of High-Density Polyethylene Materials

High-density polyethylene (HDPE) has emerged as a promising alternative to fiber-reinforced plastic (FRP) for small vessel manufacturing due to its durability, chemical resistance, lightweight properties, and recyclability. However, while thermoplastic polymers like HDPE have been extensively used in gas and water pipelines, their application in large, complex marine structures remains underexplored, particularly in terms of joining methods. Existing techniques, such as ultrasonic welding, laser welding, and friction stir welding, are unsuitable for large-scale HDPE components, where extrusion welding is more viable. This study focuses on evaluating the impact of key process parameters, such as the preheating temperature, hot air movement speed, and nozzle distance, on the welding performance of HDPE. By analyzing the influence of these variables on heat distribution during the extrusion welding process, we aim to conduct basic research to derive optimal conditions for achieving strong and reliable joints. The results highlight the critical importance of a uniform temperature distribution in preventing defects such as excessive melting or thermal degradation, which could compromise weld integrity. This research provides valuable insights into improving HDPE joining techniques, contributing to its broader adoption in the marine and manufacturing industries.

Ultrasonic joining of carbon-reinforced polyamide with oak wood for manufacturing sustainable hybrid structures

The feasibility of manufacturing strong and lightweight hybrid joints of carbon fiber-reinforced polyamide (PA6-15CF) and oak wood using ultrasonic energy was successfully demonstrated. Before joining, a groove pattern was generated on the surface of the wood platelets by laser texturing. Wood platelets with and without texturing were joined with the polymer using the ultrasonic joining (U-Joining) process. Mechanical interlocking at the polymer-wood interface was improved, as the grooves and open vessels on the surface of the textured wood platelets were filled with the polymer composite. Therefore, the lap-shear strength of joints with textured wood was 9.2 ± 0.7 MPa, whereas the shear strength of joints with untextured wood was just 4.1 ± 0.8 MPa.

Electric field enhanced diffusion welding of alloy 617: Microstructural characteristics and mechanical properties

This study investigated the microstructural characteristics and mechanical behavior of diffusion welded nickel-based Alloy 617 obtained by electric field-assisted sintering (EFAS) using various parameters. The interfacial microstructure exhibited different characteristics including good grain boundary (GB) migration across the interface in the samples diffusion-welded at 1100 °C and a flat interface in the samples joined at 1000 °C and 1050 °C. The interface consisted of fine Al2O3 oxides, while precipitation of interfacial M23C6 carbides was not observed. Grain boundaries migrated across the Al2O3 oxides, leaving these oxides within the grains. Graded grain size was observed, with grain coarsening being more significant near the sample surface due to the temperature gradient induced by EFAS. Tensile testing revealed that the specimens fractured in the matrix away from the interface, indicting strong diffusion-welded joints. The peak tensile strength of 807 MPa was obtained in the samples welded at 1000 °C due to minimal grain growth. The materials obtained at 1100 °C exhibited reduced tensile strength but improved ductility. Strain maps revealed by digital image correlation showed alternating high and low strain segments in the samples produced at 1000 °C and 1050 °C, indicating that the flat interfaces with no GB migration were less ductile compared to the matrix. A greater strain uniformity was observed along the bond interfaces with improved GB migration. The hardness reduced near the sample surfaces due to enlarged grains induced by temperature gradient. This study demonstrates that GB migration and enhanced mechanical strength can be achieved in diffusion-welded Alloy 617.

Electron beam welding of the novel L12 nanoparticles-strengthened medium-entropy alloy Ni41.4Co23.3Cr23.3Al3Ti3V6: Microstructures, mechanical properties, and fracture

Although low levels of vanadium-doping can enhance the friction stress and strength of L12-nanoparticles strengthened medium-entropy alloys (MEA), how high concentrations of vanadium affect the weldability, microstructure, mechanical properties, and fracture behavior remains unknown. In this work, we designed a vanadium-doped, L12-nanoparticle-strengthened MEA Ni41.4Co23.3Cr23.3Al3Ti3V6 (at.%), which showed a high fracture toughness of 238 MPa × m1/2, a high friction stress of 410 MPa, and a Hall-Petch strengthening coefficient of 782 MPa × μm1/2. Pieces of the HEA were joined using electron-beam welding (EBW). Strong yet ductile defect-free joints were produced which had coarse columnar grains (88 μm) with a {110}<001> texture in the fusion zone, which was larger than the equiaxed grains in the heat-affected zones (14.9 μm) which had strong {110}<001> and relatively weak {110}<112> texture. In contrast, the base materials had fine grains (2.2 μm) with a strong {110}<111> and a relatively weak {110}<112> texture. The EBWed MEA showed a high yield strength of 599 MPa, a high ultimate tensile strength of 939 MPa, a good fracture strain of 20 %, and a fracture toughness of 198 MPa × m1/2, which were 75 %, 83 %, 58 %, and 83 %, respectively, of the values of for the thermo-mechanically treated counterpart. The reduced strength arose from the coarse columnar grains, while the reduced fracture strain and fracture toughness could be ascribed to the reduced deformation twinning and the absence of annealing twins, which produced a poor strain hardening capability. The EBWed MEA exhibited abundant dislocation networks, indicating that a high concentration of vanadium inhibited the occurrence of stacking faults and nanoscale deformation twins.

Friction stir lap welding of AZ31B magnesium alloy to AISI 304 stainless steel

Abstract AZ31B magnesium alloy plates were lap-joined to AISI 304 stainless steel plates through the friction stir welding (FSW) method and utilizing various tool welding speeds. It has been found that the most important factor governing the weld strength is the hook formed on the advancing side of the welds. The weld tensile shear strength improved with an increase in the tool feed rate. Because, in general, height, length, and width of the hook taking place on the advancing side shrunk. Furthermore, the angle between the hook and interface of the plates increased, leading to reduced sharp corner formation. Apart from these, imperfections such as cavities, voids, and uncombined regions at the weld interface reduced and disappeared when increasing the welding speed. During the tensile shear test, all the welds fractured tensile mode and brittle type from the top AZ31B plate next to the hook on the advancing side. There was no breakage occurred in the weld interface, which is an indication of the strong joints. No intermetallic compounds between iron and magnesium were determined at the fracture region. At lower welding speeds, a higher amount of AISI 304 particles occurred at the weld stir zone resulting in a higher hardness.

Unveiling the Potential of Friction Stir Welding for Seamless Metal Joining

Friction Stir Welding (FSW) has revolutionized metal joining in manufacturing by offering robust joints without defects. This study examines FSW using specific parameters and evaluates its impact on mechanical properties and microstructure. Through rotational speed (2192 RPM), welding speed (36.3 mm/minute), tool tilt (3.4°), and concave shoulder angle (9°), FSW was applied to predetermined metal materials. Impact and Vickers tests were conducted post-welding to assess toughness, surface hardness, and microstructural changes. Results highlight the significant influence of FSW parameters on material properties, providing insights for optimizing efficiency and quality in the manufacturing industry. The study's findings contribute to addressing knowledge gaps and advancing FSW applications in industrial settings. Highlight: Precise Parameters: Control for strong joints in manufacturing. Toughness Evaluation: Assessing joint resilience under dynamic loads. Industry Optimization: Enhancing efficiency and quality in metal joining processes. Keywoard: FSW, Manufacturing, Mechanical Properties, Optimization, Impact Testing

A simple and efficient resin precoating treatment on anodised substrate surfaces for enhancing the adhesive bonding strength between aluminium and mild steel

The primary concerns in the adhesive bonding of metal substrate surfaces include inadequate wettability, compatibility, and insufficient mechanical interaction at the bonding interface. These factors are significant barriers to developing and manufacturing high-strength bonded materials. This study utilized three different anodising techniques, such as H3PO4, H2SO4, and NaOH, to produce micro-rough surfaces that improve the adhesive bond between aluminium alloy and mild steel. A novel and a simple method known as resin pre-coating (RPC) were used to increase the wetting and effectively seal the micro-cavities of mild steel and aluminium surfaces. RPC solution comprises 10 wt% resin (Absence of hardener) and 90 wt% acetone, which facilitated the penetration of resin into the microcavities surface, thereby increasing the bonding surfaces. Subsequently, the normal adhesive mixed with hardener is placed onto the metal surfaces. The adhesive bonding strength was evaluated by conducting the single lap shear test under various surface conditions. The surface topography of anodised samples were examined by X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM), Field Emission Scanning Electron Microscopy (FESEM), and Contact Angle Goniometer. Experimental results of a lap shear test revealed that the adhesive bond strength of H3PO4 anodised samples is greater than those of H2SO4 and NaOH anodised samples. Furthermore, the RPC treatment increased the bond strength of all H3PO4 anodised samples by 46.91–47.26 %, for H2SO4 samples by 39.71–42.22 %, and NaOH samples by 37.89–48.51 %, compared to the readings obtained without RPC treatment. The combined use of H3PO4 and RPC treatment results in the greatest bonding strength of 16.765 MPa, which is 9.17 % and 20.10 % greater than the bonding strength of H2SO4 and NaOH anodised samples. Thus, the H3PO4 anodised method improved the wetting ability of the metal surface and maximized the use of contact area on the rough substrate surfaces. The anodising treatment details in this study are inexpensive and simple for creating strong adhesive joints in aviation, automobile, and aerospace applications.

Weldability and Mechanical Properties of Pure Copper Foils Welded by Blue Diode Laser.

The need to manufacture components out of copper is significantly increasing, particularly in the solar technology, semiconductor, and electric vehicle sectors. In the past few decades, infrared laser (IR) and green laser (GL) have been the primary technologies used to address this demand, especially for small or thin components. However, with the increased demand for energy saving, alternative joint techniques such as blue diode laser (BDL) are being actively explored. In this paper, bead-on-plate welding experiments on 0.2 mm thick pure copper samples employing a BDL are presented. Two sets of parameters were carefully selected in this investigation, namely Cu-1: Power (P) = 200 W; Speed (s) = 1 mm/s; and angle = 0°, and Cu-2: P = 200 W; s = 5 mm/s; and angle = 10°. The results from both sets of parameters produced defect-free full penetration welds. Hardness test results indicated relatively softer weld zones compared with the base metal. Tensile test samples fractured in the weld zones. Overall, the samples welded with Cu-1 parameters showed better mechanical properties, such as strength and elongation, than those welded with the Cu-2 parameters. The tensile strength and elongation obtained from Cu-1 were marginally lower than those of the unwelded pure copper. The outcomes from this research provide an alternative welding technique that is able to produce reliable, strong, and precise joints, particularly for small and thin components, which can be very challenging to produce.

Multi-objective optimization method for steel frame with top-and-seat angles considering yield control

Based on the yield mechanism control principle of “strong columns and weak beams, strong joints and weak components” in steel frames connected by top-and-seat steel angles, this paper proposes a method to define the relationship between the bending capacity of various components through inequality iteration and deduction. A number of component parameters has been identified that enables control of the yielding sequence in structural components. The study also developed an objective function and used genetic algorithms to create a multi-objective optimization technique for semi-rigid steel frame structures. The method considers the non-dominated cost interval, resulting in a more comprehensive approach. From the optimization case studies against the published experimental results and finite element simulations, it demonstrates that the proposed approach efficiently manages the yielding sequence and minimizes the decision space. The optimization model provides the coordination optimization between structural cost and lateral base shear capacity.

Performance study of eccentrically braced steel frames with core tube flange connection

This paper proposes a kind of assembly brace connections adapted to the core tube flanged column connection joint of the frame-brace structure, starting from the eccentrically braced frame structure in the steel frame system and designing and completing a set of proposed static tests of the eccentrically braced frame with the core tube flanged column connection joint. By conducting in-depth analysis and research at three levels, namely the seismic performance of the eccentrically braced frame system, the performance characteristics of the core tube type flanged column connection joints, and the performance of assembled brace connections, the study has yielded insights into the force mechanism and failure modes of the core tube type flanged column connection joints within the eccentrically braced frame system; the eccentrically braced frame system has been validated to possess good seismic performance by analyzing hysteresis curves, typical section strains, and bolt forces. These analyses have shown that the system can meet the seismic requirements. Moreover, the assembled brace joints were destroyed later than the braces, indicating that the assembled brace connection joints could fulfill the requirement of “strong joints.”

Strong composite SnAgCu solder joints with internal aligned carbon fibers by magnetic field

Lightweight carbon fibers with high mechanical performance are referred to as an ideal reinforcement for an extensive variety of composite materials. However, the addition of carbon fibers into electronic interconnection solders is extremely limited so that the expected reinforcement in the mechanical properties of the composite solder joints has not been completely realized. Here, we used magnetic fields to align Ni-coated carbon fibers in the Sn-3.0Ag-0.5Cu solder vertically with the Cu substrate and prepared the oriented composite solder joints. We achieved a further improvement in the shear performance of composite solder joints (∼58 MPa) with a small addition of Ni-coated carbon fibers (0.5 wt%), which is 25% higher than that of pristine joints. It is found that these vertically oriented carbon fibers changed the propagation path of shear cracks and thus increased the shear resistance. Ni-coated carbon fibers also promoted nucleation of interfacial Cu6Sn5 in the solder joints during reflow, but prevented the formation of brittle Cu3Sn phase during isothermal aging, thus ensuring the high shear strength of composite solder joints after isothermal aging. This success provides a new pathway to fabricate a strong composite solder joint with a limited addition of reinforcements by aligning their orientation.

The possibility of application of bonded joints on different facade systems

Bonded joints in the construction industry have a rich history dating back to ancient civilisations, where they were mainly used to join materials such as wood or stone. In particular, natural materials such as bitumen or natural resins were used for this purpose. In the present modern era, with the development of adhesive technologies and synthetic adhesives, they have become an essential part of construction industry practice. Within facade cladding, bonded joints are becoming key to achieving high thermal insulation performance and overall building energy efficiency. The correct design of the building envelope is increasingly relevant in the context of the geopolitical situation starting with the global pandemic COVID-19 and the two conflicts between Russia and Ukraine and between Israel and Palestine that resulted in energy crises [1]. The paper summarizes the potential applications of adhesive bonded joints on facades, the types of adhesives used at different joints and their ability to provide strong and durable joints when exposed to different climatic conditions during summer and winter months.

Features of the structure of the lower jaw of the common hedgehog in connection with their type of nutrition

Taking into account the diet of the common hedgehog, we were faced with the question of the features of the structure of the chewing apparatus of the common hedge-hogs. We decided to study and establish anatomical, topographic and morphometric features of the structure of the lower jaw in the common hedgehog. The purpose of our study is to study the anatomical and topographic features of the structure of the lower jaw of the common hedgehog associated with the type of nutrition, as well as to establish morphometric data of the mandibular apparatus. To study the anatomical and topographic features of the structure of the mandibular bone of this individual, five corpses of the common hedgehog from the forestry of the Leningrad region were obtained. All representatives of this species were sexually mature. As a result of our research, we have established anatomical and topographic features of the structure of the lower jaw of the common hedgehog associated with the type of nutrition, and also determined the morphometric data of the mandibular apparatus. According to the results of the study, we came to the conclusion that the common hedgehog has a very powerful and well-developed lower jaw, which consists of a body and a branch. The root part of the mandibular bone is 2.10 times longer than the incisor part, and they are almost equal in width. This fact indicates the compression power of both incisor and molar teeth during biting and chewing solid food. On the incisor part there are incisor teeth in the amount of four pieces, on the root part of the body there are molars and premolars in the form of molars and premolars with a total of four pieces. Thanks to this, hedgehogs are able to easily grab food lying on the surface of the earth and chew thoroughly. The branch of the lower jaw has well-developed processes, thanks to which strong joints are formed and muscles are securely attached during the act of chewing. On the lateral surface of the lower jaw branch there is a well-defined depression that forms the pit of the large masticatory muscle, this certainly indicates the presence of highly developed masticatory muscles in this animal.

THE INFLUENCE OF VIBRATIONS ON THE MECHANICAL PROPERTIES OF WELDED JOINTS AND GAS DYNAMIC COATINGS

This article presents an in-depth analysis of the interaction of vibration processing with the mechanical properties of welded joints and gas dynamic coatings. Considering the significant impact of vibrations on metallurgical and technological processes, the key aspects of this interaction and its possible influence on the quality and durability of welded joints and coatings are considered. The article sets itself the task of determining the optimal parameters of vibration processing aimed at achieving the highest strength and elasticity in welding joints. A systematic analysis of the influence of the amplitude, frequency and duration of vibrations on the mechanical properties of materials is carried out. Analyzing the interaction of vibrations with the mechanical properties of welded joints, the article reveals the potential of using vibration processing to improve welding processes and form strong and durable joints. Special attention is paid to the study of the influence of vibrations on the microstructure of materials and their ability to withstand mechanical loads in various operating conditions. Additionally, the paper explores the interaction of vibration treatment with gas-dynamic coatings, as these coatings play an important role in providing surface protection and functionality. The authors study how vibrations can affect the uniformity of coating application, their stability and adhesion to the base. A separate aspect of the article is devoted to considering the possibilities of optimizing gas dynamic coatings using vibration processing to achieve better adhesion and stability. The study covers not only metal coatings, but also polymer and composite materials. The conclusions of the article determine the importance of taking into account the influence of vibrations on welding and coating processes, indicating the prospects for improving production technologies to increase the quality and durability of joints and coatings in industrial applications.

Optimizing joint structure and performance in friction spot joining of aluminum alloy AA6061 and poly-ether-ether-ketone (PEEK)

This study investigated the challenge of joining poly-ether-ether-ketone (PEEK) to aluminum alloy AA6061 through friction spot joining (FSpJ), by examining the impact of surface treatment of AA6061 sheets and analyzing various process parameters' effects on joint interface morphology, tensile-shear strength, and failure. Results indicated a peak interface temperature may reach 400 °C during FSpJ, with a 0.5–0.9 mm molten PEEK layer containing sealed bubbles. Notably, Boehmite treatment significantly improved joint strength, although the primary failure occurred in the PEEK base material. An optimization through response surface method (RSM) analysis identified plunging depth as the most influential factor in joint strength, and a peak load of 4576 N with an optimized combination of pin rotation speed, plunging depth, and dwell time was achieved. Using optimized process parameters, strong PEEK-AA6061 joints can be formed, and the approach is extendable to joining other metallic and polymeric materials.

Prediction of static failure in metal inert gas welded nuclear grade pipe 347 SS: Experimentation and finite-element analysis approach

Defect repair, one of primary concerns in the maintenance system for pipelines and other high strength components, is crucial in improving the reliability and economic benefits. Even though modern industries use several welding techniques to join metals, metal inert gas (MIG) welding is frequently preferred to weld stainless steel components by producing strong joints at high speed. In this study, MIG welding was used to butt weld 347 SS pipes. Research related to material failure is critical to engineers in order to find suitable application. Tensile test provides the static behavior of material. Therefore, predicting the strength and failure of material helps in satisfying industrial needs. Finite-element analysis (FEA) is an efficient technique to predict physical phenomenon virtually, therefore reducing the need for real-time prototypes. Johnson-Cook (J-C) material failure model is utilized to define failure in FEA model. Error percentage obtained while comparing FEA and experimental results of weld metal is 1.03%. Presence of niobium carbide is evident through the line map of energy-dispersive X-ray spectroscopy spectrum which prevents knife line attack through retarding chromium carbide precipitation at high temperature cycles. Welded samples with tensile strength of 583 ± 3 MPa exhibit better mechanical strength than base metal with tensile strength of 575 ± 2.5 MPa. This change in mechanical properties is caused by microstructural variation led by occurrence of constitutional supercooling while melt-pool solidifies. Failure mechanism of ductile fracture is understood from fractography (Tensile sample). Hence, this study provides a complete knowledge on failure mechanism of MIG-welded nuclear grade steel pipe under static loading. The failure mechanisms are explained in terms of FEA (J-C model) and fractography.

Electron beam welding of L12-nanoparticle-strengthened strong and ductile medium-entropy alloys for cryogenic applications

The weldability, microstructures, and mechanical properties of two L12-nanoparticle-strengthened medium-entropy alloys (MEAs) Ni43.4Co25.3Cr25.3Al3Ti3 and Ni42.4Co24.3Cr24.3Al3Ti3V3 (at.%) are explored after electron beam welding (EBW). Strong yet ductile defect-free joints were produced with coarse columnar grains (118–245 μm) in the fusion zones, which were larger than the equiaxed grains in the heat-affected zones (15.6–22.3 μm) and in the base materials (4.6–5.6 μm). Both EBWed MEAs showed high yield strengths (838–858 MPa), high ultimate tensile strengths (1416–1420 MPa), and good fracture strains of 20–21 % at 77 K, which are 66∼83 %, 84–89 %, and 57–81 %, respectively, of those of the respective thermo-mechanically treated (TMT) MEAs. The V-doping improved the cryogenic mechanical properties of the TMT MEA while not influencing those of the EBWed MEA. High back-stress hardening contributes to over 50 % of the cryogenic strength. Both EBWed MEAs exhibited abundant dislocation networks, stacking faults, and nanoscale deformation twins after fracture, producing a high strain hardening rate and good ductility.

Evaluation of wear test on functionally graded metal-polymer tri-laminate composite interfaces of cooling-assisted friction stir additive manufacturing

In this study, a new friction stir welding (FSW) based additive manufacturing (AM) process called "cooling-assisted friction stir additive manufacturing (CA-FSAM)" was introduced to join sheets of metal-polymer hybrid structures (MPHS). Dry ice was introduced as the coolant. Thickness variations of the raw high-density polyethylene (HDPE) and 5083 aluminum alloy (Al5083) sheets were functionally graded at a rate of 0.75 mm from the former layer. The arrangement of layers in terms of thickness was arranged in the order of 3, 2.25, and 1.5 mm. Functionally graded metal-polymer tri-laminate composite fabricated with CA-FSAM technology was investigated using the pin-on-disk wear test. The results showed that mechanical locking between the layers affected the bond strength. Cross-sectional morphology examination revealed defect-free, strong joints. X-ray diffraction (XRD) results confirmed the formation of Mg2Si; however, the XRD peak was low, indicating a slight effect on the interface properties. Thermal gravimetric analysis (TGA)-Fourier transform infrared spectroscopy (FT-IR) characterization highlighted that the main evolved products during tri-laminate composite joining were CO, CC, CH3, CH2, and CH2. Oxidation occurred in the FTIR peak in the absorption band (1029.92 cm−1 to 1370.63 cm−1). Disk loading resulted in the buildup of an internal drag force that caused the dislocation/rupture of the CC or CH bonds. Defects, such as deep grooves, pits, and delamination at the interface, were observed in the composite specimen. The wear path was not visible in the worn composite material. The wear rate at 4 kg load on Al5083, HDPE, and metal-polymer tri-laminate composite specimens was 3.15 ± 0.22, 4.72 ± 0.36, and 3.42 ± 0.18 × 10−6 mm3/N. m, respectively.

Thin lamellar films with enhanced mechanical properties for durable radiative cooling

Passive daytime radiative cooling is a promising path to tackle energy, environment and security issues originated from global warming. However, the contradiction between desired high solar reflectivity and necessary applicable performance is a major limitation at this stage. Herein, we demonstrate a “Solvent exchange-Reprotonation” processing strategy to fabricate a lamellar structure integrating aramid nanofibers with core-shell TiO2-coated Mica microplatelets for enhanced strength and durability without compromising optical performance. Such approach enables a slow but complete two-step protonation transition and the formation of three-dimensional dendritic networks with strong fibrillar joints, where overloaded scatterers are stably grasped and anchored in alignment, thereby resulting in a high strength of ~112 MPa as well as excellent environmental durability including ultraviolet aging, high temperature, scratches, etc. Notably, the strong backward scattering excited by multiple core-shell and shell-air interfaces guarantees a balanced reflectivity (~92%) and thickness (~25 μm), which is further revealed by outdoor tests where attainable subambient temperature drops are ~3.35 °C for daytime and ~6.11 °C for nighttime. Consequently, both the cooling capacity and comprehensive outdoor-services performance, greatly push radiative cooling towards real-world applications.

Optimization of FSW parameters on bio-inspired jigsaw suture patterns to improve the tensile strength of dissimilar thermoplastics

This study aimed to enhance the Tensile Strength (TSFSW) of dissimilar thermoplastic joints by utilizing a bio-inspired jig saw suture and optimizing the Friction Stir Welding (FSW) limits are Traverse Speed (TS) and Plunge Depth (PD) and Rotational Speed (RS) at three varied levels. Statistical analysis, response surface methodology (RSM), and experimental validation were involved in achieving the research objectives. The outcomes showed that the TS and PD parameters had a higher significance on Tensile Strength compared to RS. The RSM prediction results were validated through experiments, achieving an extreme Tensile Strength of 11.1 MPa with a low error percentage. The best values of the FSW limits were found to be Rotational Speed (RS) of 1200 rpm, Plunge Depth (PD) of 0.37 mm, and Traverse Speed (TS) of 49.39 mm min−1. The formulated mathematical model with regression co-efficient R2 of 0.96 and RSM proved effective in predicting the optimal FSW parameters and achieving superior TSFSW. These findings prove that combination design can be reliably applied to optimise with a 95% confidence interval. The optical microscope and SEM morphological results in this study make congruently accurate predictions for the joint of the tensile fracture zone. These findings contribute to the advanced FSW techniques for dissimilar thermoplastic joints, providing insights for industrial applications requiring strong and reliable joints.