Friction Welding Process Research Articles

Finite Element Simulation and Experimental Analysis of the Thermo-Mechanical Properties of Dissimilar S275 and 316L Austenite Stainless Steels using the RFW Process

This research examines the effect of thermomechanical and microstructural constituents on welding of AISI 316L (austenite stainless steel) and S275 steel. A Finite Element Model (FEM) was constructed using ANSYS 19.1, and an experimental study was conducted using the Rotary Friction Welding (RFW) process. It was determined that there is a genuine correlation between the simulation FEM and the experimental procedure with regard to the thermal profile and ultimate yield strength, particularly when a welding speed of 2,000 rev/min is employed. At that speed, the higher temperature recorded and calculated was 1,450 oC. The discrepancy between the numerical FEM and the experimental temperature profile for the peak temperature calculation was determined to be 2.78%. The mechanical analysis was conducted through tensile force calculations and experiments, the results of which indicated an estimated error of 12%. The calculated error for the ultimate yield strength of the various samples is less than 6% for tensile strength. Upon tensile testing, failure occurred in the S275 sample. The microstructure exhibited increases in Cr and Ni of 1.2% and 1.01%, respectively, in comparison to the base metal of 316L stainless steel.

An energetic approach to the statistical analysis and optimization of friction welding processes applied to an aluminum-steel-joint

The present publication deals with an energy-oriented approach to the statistical analysis of rotational friction welding processes. To illustrate the methodological approach, it is applied to investigate the effects of energy flow on material flow behavior and joint quality during friction welding of an AA6060 alloy with a low-alloy 16MnCr5 filler steel. The influences of the setting parameters on the energetic states are first analyzed by means of an initial screening. The evaluation using process simulation and statistical methods enables the generation of regressive response surfaces for the friction power, the friction time and the resulting induced friction energy. Based on these findings, a second experimental field is formed and evaluated, which considers the interaction between the energy input of the frictioning stage and the workpiece forging. This new approach results in the functional separation of the frictioning and forging stage, which eliminates the usual statistical interaction effects and thus facilitates analysis and optimization. The qualitative result variable required for the purpose of interpreting the results is the ultimate tensile strength of the friction-welded joint. Additionally determined hardness curves provide information about the properties of the thermally influenced zone and strength-relevant process sequences. The result is that, in addition to the amount of energy induced, the frictional power with which the former is induced also has a considerable influence on the joint strength, as it influences the material flow and the properties of the joining zone.

The Effect of Periodic Friction and Upsetting Pressure on Rotary Friction Welding Process

The Effect of Periodic Friction and Upsetting Pressure on Rotary Friction Welding Process

Interfacial inhomogeneous plastic deformation during rotary friction welding of dissimilar AA2219-SS321 joint combination with AA6061 interlayer

This research investigates the inherent radial non-uniformity within the rotary friction welding process, particularly concerning microstructure attributes like grain size, grain boundaries, misorientation angles, and interlayer presence along the radial axis. SS321-AA2219 rotary friction welding was carried out with and without an AA6061 interlayer. The numerical thermal model suggests increase in temperatures from the center to the periphery, due to non-uniform heat generation. Also, dissimilar material across the interface resulted in an asymmetric temperature profile along axial direction. Plastic deformation on the Aluminum side suggests dynamic recrystallization and grain refinement, whereas pronounced low-angle grain boundary (LAGB) formation near the SS side interface validates dynamic recovery. A radial non-uniformity in microstructure is observed, with metrics such as average grain size, LAGB fraction, and misorientation showing an increase from the center towards the periphery. The insertion of an interlayer alters process dynamics, manifesting in reduced temperatures and heightened forces, resulting in a more consolidated joint by enhancing the strength by 31 %. Interdiffusion of elements across the interface formed Fe-Al intermetallic compounds (IMC) confirmed with X ray diffraction. Fractography analysis elucidates the presence of rubbing marks and facet surfaces in interlayer-less joints, while joints with interlayer display sticking and dimples.

Comparison of Warm and Cold Forging with Friction Welding for Inner Constant Velocity Joints (CVJs)

Driveshafts are used in all vehicles, and their service life is expected to be at least three years or 100.000 km. Many driveshaft manufacturers prefer friction welding due to its relatively cheaper cost and ease of the process. However, they should meet some property-related criteria to achieve the expected lifetime. The forging technique becomes essential to succeed in these mechanical requirements. A comparative study evaluates the performance of constant velocity joints (CVJs) produced by multi-step warm–cold forging and friction welding processes. Medium carbon steels were used in both of the techniques. The microstructures, mechanical properties (i.e. hardness, strength, impact energy and shear strength), low-cycle fatigue (LCF) properties, wear resistance and cost-efficiency (number of operations, material saving, number of produced components and cost) are compared in detail for an industrial production point of view. The experimental results reveal that warm–cold forged specimens exhibit superior mechanical properties such as increased strength, hardness, relatively higher impact energy, improved shear strength, relatively longer LCF life and enhanced wear resistance (lower wear volume loss). In addition, it is also assessed that warm–cold forging is a more cost-effective manufacturing process (reduced weight, decreased number of operations and increased yield) in the production of CVJs compared to the friction welding process.

Continuous Drive Friction Welded Al/Cu Joints Produced Using Short Welding Time, Elevated Rotational Speed, and High Welding Pressures.

The present study aimed to enhance the efficiency and efficacy of the Al/Cu joint production process implemented by the company VEMID Ltd., Jagodina, Serbia, by attaining sound joints within a very short welding time. For this purpose, the present study aimed at investigating the accuracy and the quality of the continuous drive friction welding (CDFW) process, as well as the optimum combination of CDFW parameters with highest joint efficiency in terms of investigated properties. The accuracy was estimated through an analysis of temperature-time curves recorded during CDFW using an infrared camera. The quality was evaluated through an investigation of the properties of Al/Cu joints produced using different friction (66.7, 88.9, and 133.3 MPa) and forging (88.9, 222.2, and 355.6 MPa) pressures and a constant total welding time (4 s) and rotational speed (2100 rpm). Thermal imaging with an infrared camera demonstrated that the actual total welding time was 15% longer compared to the nominal value. This was attributed to the slow pressure response of the pneumatic brake system. The relative changes in the maximum surface temperature (TMS) during the CDFW process corresponded to changes in welding pressures, indicating the potential of the thermal imaging method for monitoring and assessing this process. A preliminary investigation demonstrated that Al/Cu joints produced using welding pressures less than 88.9 MPa often displayed the presence of non-joined micro-regions at the Al/Cu interface and a significant thickness of interfacial Al2Cu (up to 1 µm). However, when friction pressure was set at 66.7 MPa, an increase in the forging pressure to 222.2 MPa eliminated the presence of non-joined micro-regions and reduced the thickness of Al2Cu to 0.5 µm on the average level. These Al/Cu joints achieved the highest joint efficiencies in terms of strength (100%) and ductility (61%). They exhibited an electrical conductivity higher than 92% of the theoretical value. A further increase in any welding pressure produced similar or deteriorated properties, accompanied by an increase in the consumption of raw materials and energy. Such turn of events was counterproductive to the original goal of increasing the efficiency and efficacy of the CDFW process.

Experimental Investigation of Material Flow and Welding defects in Friction Welding process of Cu-SS Dissimilar Materials

Abstract: A particular form of welding that makes use of the heat produced by friction is called friction welding. A pressure force contacts the surfaces of two materials that need to be connected; one is rotating while the other is at rest. In order for the heat produced by the continuous friction to continue rising, friction is applied continually to the second contact surface. In this study, dissimilar friction welding between grade 308 L stainless steel (SS) and copper (Cu) is investigated for a pipe joint design with a wall thickness of 1.50 mm and an outer diameter of 13 mm. The machine RPM, dwell duration, friction time, and friction force are the constant parameters that are used. The maximum ultimate tensile strength of 764 MPa, or almost 128% of the SS base material, was found in the SS to SS weld sample and 104 MPa, or nearly 80% of the Cu basis material, in the CU to CU weld sample. The most significant maximum tensile strength of 349 MPa was achieved by SS to Cu. In along with the study of the mechanical behavior and microstructure, the weld quality was evaluated using corrosion behavior analysis and leak proof testing.

Fatigue Strength Assessment of Friction Welds under Consideration of Residual Stress.

A reliable local-fatigue assessment approach for rotary friction-welded components does not yet exist. The scope of this paper is to present test results for the fatigue behaviour of rotary friction-welded solid shafts made of structural steel S355J2G3 (1.0570) and an approach to fatigue assessment considering residual stress. In contrast to fusion-welded joints, components made by rotary friction welding usually contain compressive residual stress near the weld, which can significantly affect the fatigue strength. For this purpose, specimens were welded and characterised, including metallographic micrographs, hardness measurements, and residual stress measurements. The fatigue tests were performed with a constant amplitude loading in tension/compression or torsion with R = -1. All specimens were investigated without machining of the weld flash, either in the as-welded state or after a post-weld stress-relief heat treatment. In addition, the friction welding process and the residual stress formation were analysed using numerical simulation. The characterisation results are integrated into a fatigue assessment approach. Overall, the specimens perform comparatively well in the fatigue tests and the experimentally observed fatigue behaviour is well described using the proposed local approaches.

PENGARUH LAMA WAKTU TAHAN NORMALIZING PADA BAJA ST 41 PENGELASAN FRICTION WELDING TERHADAP SIFAT MEKANIS

The development and application of science and technology, especially in the industrial world, is currently experiencing very rapid progress, especially in the world of welding. Welding is the process of joining two or more metal parts using heat energy. In the current era, welding developments are increasingly developing, such as liquid welding, resistance welding, solid welding, and forging welding. For solid welding, there are friction welding and cold welding. The joining process using friction welding involves friction factors, pressing force, and surface quality. To improve the mechanical properties of steel after welding, Normalizing heat treatment is carried out, namely a heat treatment process on steel which aims to refine the grain, homogenize the structure and obtain steel with mechanical properties as desired, or called normalization. This research method uses the Experimental Testing method. This sample was obtained from the normalizing friction welding process which was tensile tested, namely samples with varying holding times of 15 minutes, 30 minutes and 45 minutes with an engine speed of 2100 rpm and a pressure of 35 MPa with tensile testing of the material and microphotographs. The results of the friction welding research are as follows. The normalizing holding time of 15 minutes produces a maximum tensile stress value of 325.16 N/mm2, the fracture that occurs is in the form of a ductile fracture, the normalizing holding time of 30 minutes produces a maximum tensile stress value of 327.66 N/mm2, the fracture that occurs is in the form of a fracture ductile, the normalizing holding time of 45 minutes produces a maximum tensile stress value of 329.53 N/mm2, the fracture that occurs is in the form of a ductile fracture. The long holding time of normalizing will increase the tensile strength of the steel and tensile test fractures mostly occur in the weld area

Role of oscillation frequency and amplitude on the microstructure and properties of linear friction welded nickel aluminium bronze joints

This study explores the influence of oscillation frequency and amplitude on the quality of linear friction welded joints using as-cast nickel aluminium bronze. Welding was conducted at 30 Hz, 50 Hz, and 70 Hz oscillated frequencies and amplitudes of 1.5 mm, 2 mm, and 3 mm. The joint’s performance was thoroughly investigated through systematic analysis, including macrostructure examination, peak interfacial temperature measurement, microstructure evaluation, strain assessment, cooling rate determination, microhardness testing, and tensile property characterization. The width of the weld zone varied from 183 μm to 297 μm, and the thermomechanical affected zone (TMAZ) area ranged from 4.48 mm2 to 14.79 mm2 across different process parameters. In the parent material, the volume fraction of the β-phase was as low as 20.2%, contrasting with the dominant α-phase at 79.8%. The average grain size of the lamellar and globular α-phase mixture was 26.4 μm. Notably, the weld zone exhibited extremely refined α-phase grains, with diameters less than 5 μm in all cases. The volume fraction of the β‘-phase increased significantly with higher frequencies, from 15.299% at 30 Hz to 26.98% at 50 Hz, peaking at 40.08% at 70 Hz, leading to varying k phases. This variation in microstructure had a substantial impact on mechanical properties. Tensile strength ranged from 503 MPa to 582 MPa, while ductility varied from 13.5% to 21.7%. Additionally, the hardness of the parent material increased from approximately 155 Hv to 260 Hv. This study demonstrates that controlling the oscillation frequency and amplitude in linear friction welding processes can yield consistent, high-quality welds in nickel aluminium bronze.

Friction Welding Processes: A Review

Friction welding is a sort of solid-state welding process that does not use flux, shielding gases, or filler metal; instead, the heat needed to fuse the materials is produced by the friction between two or more objects moving relative to one another. This kind of welding is an alternative to the traditional fusion and adhesive-based welding procedures. The method is reliable, capable of joining materials that would seem hard to join with traditional welding, and suitable for joining both similar and dissimilar materials including wood, steel, aluminum, copper, masurium, nickel, zinc and carbon steel. Friction welding can be carried out by using several techniques including linear, rotary, friction stir, direct drive and inertia welding. Each of these welding techniques is distinct and are named according to the relative motion involved. Although the process varies slightly subject to the type of motion, the procedure is consistent and the resultant joint is comparable with those obtained through conventional welding technique. This study reviews the distinct friction welding processes and specific techniques involved in the process.

Rotary friction welding of 304 stainless steel: parametric study, mechanical properties, and microstructure of the joint

In the rotary friction welding process, the selection of process parameters affects the friction, heat generation, and joint formation. These factors collectively cause microstructural changes that determine the mechanical properties of the joint. Therefore, the process parameters, microstructure, and mechanical properties were interconnected during rotary friction welding. This study examined the influence of process parameters on their correlation with microstructure and mechanical properties in the rotary friction welding of 304 SS. A 3×4 full factorial experimental design was used to evaluate the effects of the process parameters on the microstructure and strength of 304 SS joints produced through rotary friction welding. An accurate evaluation of joint strength was performed using the notch tensile test technique. The joint with the highest strength was achieved by applying a combination of friction pressure and friction time at 55 bars and 3 seconds, respectively, resulting in a welding efficiency of 103.6%. A very low friction time (i.e., 5 s) produced a weak joint, which should be avoided. The welding process created three distinct structural zones in the joint: a joint structure finer than the parent metal structure, a partially deformed structure, and a heat-affected zone with deformation. Hardness tests of the joints showed a high hardness in the deformed structure. The formed structure contributes to the resulting joint strength.

Characterisation of rotary friction welding process and mechanism of heat-treated Scotch pine

Rotary friction welding of wood to heat-treated lumber from Scotch pine is feasible and the strength of the joint exceeds that of glued and hammered joints. This study investigated the rotary friction welding process parameters and its welding mechanism applicable to heat-treated Scotch pine. Untreated Scotch pine served as the control. The one-way test revealed the tenon/bore ratio of 1.5, rotational speed of 2000 to 3500 r/min, and feed rate of 15 to 20 mm/s as the ideal process parameters for heat-treated Scotch pine. Under the same conditions, heat-treated material had weld strength up to 63.2% higher than untreated material. The portion of the weld zone with better weld strength was larger in size, had a full surface, and was darker in color, according to ultra-depth-of-field microscopic examinations. The internal wood components melted and cooled after the welding was finished and re-polymerized to form a tightly wrapped structure, linking the dowel rods to the substrate, according to the results of scanning electron microscopy.

Mechanical Properties of the AlCu4Mg1 Alloy Joint Manufactured by Underwater Friction Stir Welding.

The manuscript presents the results of butt joining of 3-millimeter-thick AlCu4Mg1 alloy sheets using the FSW (friction stir welding) and UWFSW (underwater friction stir welding) methods. The aim of the research is to verify the influence of the water environment on the FSW friction welding process. The article checked three sets of joint parameters. The parameters differed in tool rotation speed and feed rate. The same sets of parameters were used for the FSW and UWFSW fusion techniques. With the supplied devices, metallographic sections are cross-sectioned, and the power supplies are subjected to a light microscope. Microhardness tests and the influence of the heat-affected zone were carried out. A monotonic test was performed. A monotonic test is available, extended with a visual correlation test. The obtained cracked fracture surfaces were examined using a scanning microscope. An analysis of the microfractographic cracking process was carried out. The obtained results did not show any improvement in the strength properties of the obtained joints made using the UWFSW technique when using a scanning microscope.

Experimental and FEM Studies of Continuous Drive Friction Welding of Ferritic Spheroidal Graphite Cast Iron

Experimental and FEM studies of the friction welding process of spheroidal graphite cast iron (SGCI) are presented. A coupled thermal and mechanical 2.5 D FEM model was used to simulate the continuous drive friction welding (CDFW) process. The FE model predicted the peak temperature of the joint, effective stress, axial shortening, and the weld flash size. Additionally, the friction force on the axial shortening of specimens was studied. The peak temperatures were measured both on the axis and at the surface of the specimen. The predicted maximum temperatures in the axis, ½ radius, and 2 mm from the surface of the sample amounted to 1162 °C, 1177 °C, and 1061 °C, respectively. The maximum temperature of the spheroidal graphite cast iron joint was below the melting temperature of the base material (~1350 °C). The predicted temperature curves, outbursts, and shortening of welded elements indicated a good match with real models.

Thermomechanical and microstructural simulation of rotary friction welding process of Inconel718 alloy using the finite element method

Thermomechanical and microstructural simulation of rotary friction welding process of Inconel718 alloy using the finite element method

The Experimental and FEM Studies of Friction Welding Process of Tungsten Heavy Alloy with Aluminium Alloy

Experimental and finite element studies of the rotary friction welding (RFW) process of tungsten heavy alloy (THA) with aluminium alloy 5XXX series are presented. A 2.5D torsion simulation model including the circumferential effects was developed in this study. The temperature distributions, effective stress, flash dimensions and axial shortening were calculated on un-rotated friction welding aluminium parts. The peak temperatures were measured both in the axis and at the half-radius of the specimen. The maximum interface temperature of 581 °C for the friction weld was below the melting temperature of the aluminium alloy. The experimental and numerical results of the temperature and final weld geometries show good agreement between them. The results indicate very small deviations of 4.45%, 2.96%, and 2.34% on the flash width, flash height and axial shortening of friction welds.

Thermal-Mechanical and Microstructural Simulation of Rotary Friction Welding Processes by Using Finite Element Method.

Rotary friction welding is one of the most crucial techniques for joining different parts in advanced industries. Experimentally measuring the history of thermomechanical and microstructural parameters of this process can be a significant challenge and incurs high costs. To address these challenges, the finite element method was used to simulate thermomechanical and microstructural aspects of the welding of identical superalloy Inconel 718 tubes. Numerical simulation results were used to compute essential mechanical and metallurgical parameters such as temperature, strain, strain rate, volume fraction of dynamic recrystallization, and grain size distribution. These parameters were subsequently verified using experimental test results. The Johnson-Avrami model was utilized in the microstructural simulation to convert thermomechanical parameters into metallurgical factors, employing a FORTRAN subroutine. The calculated thickness of the recrystallization zone in the wall was 480 and 850 μm at the tube wall's center and edge, respectively. These values were reported from experimental measurements as 500 and 800 μm, respectively. The predicted grain size changes from the center to the edge of the wall thickness, near the weld interface, ranged from 2.07 to 2.15 μm, comparable to the experimental measurements ranging from 1.9 to 2.2 μm. Various curves are also presented to explore the correlation between thermomechanical and microstructural parameters, with the experimental results revealing predictable microstructure evolutions correlated with thermomechanical changes.

APPLICATION OF FRICTION WELDING FOR PUMP DESIGN AND MANUFACTURING: A COMPREHENSIVE REVIEW

The discussion regarding the balance between economical and performance for the pump design and manufacturing has been increasing in recent years. Of many intelligent innovations, the use of less costly materials for pump shaft is an interesting solution for the pump design. This solution can also be achieved by selecting less costly materials made from metal. Then, the less costly metal connected to electrical motor is joined with a more costly metal connected to the pump. Since both metals can be difference ones, an advance welding process to join both metals is then required. The friction welding process is expected to fulfill this requirement. In the friction welding, heat is generated during friction between these two dissimilar metals. The generated heat should achieve particular temperatures so that the two dissimilar metals can be joined. There are three types of friction welding, e.g. the stir friction welding, the linear friction welding and the continuous drive friction welding, which can be selected to join these two dissimilar metals. This paper is based on the authors’ experience and literature review to discuss the application of friction welding for the pump design and manufacturing.

Preliminary study on effect of inertia and continuous friction welding on mechanical properties of SS 316-Zn alloys friction welded joint

The effect of inertial friction welding and continuous drive friction welding in joining SS 316 with Zn alloy is discussed in this article. Scanning electron microscopy was utilized to investigate the microstructure of the welding interaction. Energy-dispersive spectroscopy was utilized to identify the chemical composition of the element distribution at the interface. The findings reveal that a continuous drive friction welding process may produce SS 316 welded joints with Zn alloy. With a friction time of 35 s, the joint's tensile strength may reach 60 MPa. During the tensile test, all friction-welded samples failed at the interface. The fracture surface shows an almost flat surface and is not fibrous or brittle. Meanwhile, a new reaction layer from the intermetallic compound layer is not formed at the joint interface. The decrease in hardness in Zn alloys is due to the thermal softening effect caused by continuous heat from friction.