Welding Of Dissimilar Materials Research Articles

Extrinsic-Riveting Friction Stir Lap Welding of Al/Steel Dissimilar Materials.

To obtain high-quality joints of Al/steel dissimilar materials, a new extrinsic-riveting friction stir lap welding (ERFSLW) method was proposed combining the synthesis advantages of mechanical riveting and metallurgical bonding. SiC-reinforced Al matrix composite bars were placed in the prefabricated holes in Al sheets and steel sheets, arranged in a zigzag array. The bars were stirred and mixed with Al sheets under severe plastic deformation (SPD), forming composite rivets to strengthen the mechanical joining. SiC particles were uniformly dispersed in the lower part of the welding nugget zone (WNZ). The smooth transition between the SiC mixed zone and extrinsic-riveting zone (ERZ) ensured the metallurgical bonding. The maximum tensile shear load of the joints reached 7.8 kN and the maximum load of the weld per unit length was 497 N/mm. The fracture occurred at the interface between the rivets and steel sheets rather than the conventional Al/steel joining interface. Moreover, ERFSLW can prolong the service life of joints due to three fracture stages. This method can be further extended to the welding of other dissimilar materials that conform to the model of "soft/hard".

Effect of Preheating and Post-Heating on the Microstructures and Mechanical Properties of TC17-Ti2AlNb Joint with Electron Beam Welding.

To enhance welding quality and performance, preheating and post-heating are usually employed on high-temperature materials, concurrently with welding. This is a novel technique in vacuum chamber electron beam welding (EBW). TC17 and Ti2AlNb alloys are the hot topics in aero-engine parts, and the welding of dissimilar materials is also a broad prospect. To settle welding cracks of Ti2AlNb, EBW with preheating and post-heating was investigated on TC17 and Ti2AlNb dissimilar alloy, which improved the manufacturing technology on high-temperature materials. The dissimilar joint no longer had cracks after preheating, which exhibited excellent welding stability and metallurgical homogeneity, and preheating and annealing had an important effect on mechanical properties. The joint strength after 630 °C annealing is higher than that of TC17 alloy base metal (BM) and other annealing temperatures, reaching 1169 MPa at room temperature and 894 MPa at 450 °C tensile condition. The joint plasticity after 740 °C annealing is equivalent to TC17 BM. EBW with preheating improved the microstructure characteristics and enhanced the plasticity of Ti2AlNb alloy weld and dissimilar joint, which would contribute to the application of Ti2AlNb alloy and Ti2AlNb dissimilar parts.

Dual‐beam lasers meet challenges of the automotive industry

AbstractThe challenges of transport electrification require the adoption of new manufacturing techniques. Lasers excel in most difficult tasks due to their ability to deliver energy with great precision, and their temporal and spatial control. Dual‐beam, adjustable mode beam (AMB) technology enables the versatile spatial control of laser energy deposition, providing wide process windows for defect‐free welding and focal spot positioning. The AMB technology improves process quality and speed in dissimilar material welding, copper welding and in structural aluminum welding across many applications in the automotive industry – from the production of batteries and drivetrains to structural body parts.

Experimental Investigation on the Effect of Nickel-plating Thickness on Continuous-wave Laser Welding of Copper and Steel Tab Joints for Battery Manufacturing

The welding of dissimilar materials, such as copper and steel, holds significant industrial significance in the production of electric vehicle batteries. These materials are commonly used in the case of connections between busbars and cylindrical cells inside a battery pack. To optimize welding and guarantee protection against corrosion, nickel is commonly used in the form of a coating. In this paper, the effect of nickel plating thickness on copper-to-steel welds made with laser technology is investigated. The initial phase consists of a statistical characterization of the nickel plating thickness of the busbar in order to identify the thickness ranges. Experiments were conducted using two different fiber laser sources (a single-mode laser source and a beam-shaping laser source) equipped with a Galvo scanner head; the fluence value and the thickness of nickel plating varied during the experiments. The study conducted has revealed that the thickness of nickel plating plays a crucial role in the weld bead interface, particularly when using a single-mode source. Furthermore, when using the beam-shaping laser source, the fluence employed can have a significant impact on both the depth of penetration and the interface width.

Design of field shaper suitable for plate and experimental research on welding of dissimilar materials

Magnetic pulse welding realizes solid-state connection through a high-speed collision of materials, which can effectively overcome the welding difficulties of light metal materials. In the magnetic pulse welding system, in order to improve the welding efficiency, a field shaper is usually applied between the multi-turn coil and the workpiece to concentrate the magnetic field in the welding area, thereby improving the electromagnetic force. However, a large number of researchers are currently on the tube-welded field shaper, and very few researchers have studied the structure of the plate-welded field shaper. Therefore, this paper proposed a new field shaper for plate welding. The effect of the structure parameter of the field shaper on the magnetic field and electromagnetic force on the aluminum plate was analyzed in the COMSOL multiphysics software. The optimal structure parameters of the field shaper were selected. The plastic deformation and the generation of jets under different voltages and the welding of the same/dissimilar metal materials at different standoff distances were studied experimentally, which verifies the feasibility of the new field shaper.

Study on the interfacial microstructure evolution of aluminum and CFRTP on FSLW joints: influence of pin length

Polymer/metal hybrid lightweight structures are increasingly employed in automotive, aerospace and electronics industries. Friction stir welding (FSW) is applied for the effective welding of metals and thermoplastic materials. For the welding of dissimilar materials, due to the significant property differences, it is hard to achieve high strength welded joints with smooth appearance. In this article, the influence of pin length is studied by experiments for the friction stir lap welding (FSLW) of Al alloy and carbon-fiber-reinforced thermoplastic (CFRTP). Tensile tests, OM, SEM and EBSD are carried out to evaluate the welding performance. Results indicate that the joint with smooth surface topography is obtained at the pin length of 2.5 mm with a peak temperature of 250.3 °C and the CFRTP matrix PEI thermal decomposition temperature residence time of 47.6 s. From OM and SEM micro analysis, the width of the bonding area is 3.02 mm and a thin uniform interaction layer is formed in the joint. EBSD confirms that the Al alloy in the stirring zone is refined after recrystallization. It is difficult to form a stacked layered structure in the bottom of joint, so the property of the joint is improved. The tensile strength is 32.9 MPa, which is 63.1% of CFRTP.

The characteristics extraction of weld seam in the laser welding of dissimilar materials by different image segmentation methods

The characteristics extraction of weld seam in the laser welding of dissimilar materials by different image segmentation methods

An innovative coil for magnetic pulse welding of dissimilar sheet metals: Numerical simulation and experiments

Magnetic pulse welding (MPW), as an environmentally friendly room temperature solid-state welding technology, usually involves low energy utilization efficiency, resulting in the need for higher energy to achieve metallurgical welding. This study proposed an innovative coil structure for increasing energy utilization efficiency during MPW. The current signal and structural strength of new coils with different turns were analyzed by numerical simulation. The results show that, different from traditional E-shaped and H-shaped single turn coils, the new structure can achieve nearly n-time amplification of current, which enabling the flyer plate to achieve the critical speed of metallurgical welding at lower energy. The 7-turn coil has higher structural strength and pulse current compared to the other coils in this study. The initial current was amplified 5.2 times by the 7-turn coil and welding of Al-Fe plates was achieved. The microstructures at the welding interface exhibit typical metallurgical features, including wave interfaces, element diffusion layers, and intermetallic compounds. The fracture location of the AA1060 (thickness δ: 0.5)-DP600 joint appeared on the base metal. The fracture morphology of AA5754 (thickness δ: 1.0)-DP600 joint shows that a large amount of aluminum element remains on the DP600 plate. Therefore, the new coil can increase the energy utilization rate during the welding process and achieve stable metallurgical welding of dissimilar materials.

Electron-Beam Welding Joint Strength of Dissimilar Materials

This paper provides an in-depth discussion of the joint strength of electron beam welding of dissimilar materials. The effect of welding parameters and material properties on the joint strength was analyzed, and an argument for the optimal parameter combination is presented. Electron-beam welding technology offers several advantages, including high energy density and the ability to create fine weld seams. However, it also presents certain challenges, such as the complexity of welding parameters and the potential generation of brittle phases. The analysis conducted in this paper holds significant importance in enhancing the quality and efficiency of dissimilar material welding processes.

Numerical investigation of the impact of thermoelectric effect on electron beam welding of dissimilar materials

Electron beam welding of GH4169 and Ni is required in the manufacture of the regenerative cooling system of the liquid rocket motor. The thermoelectric effect is observed during the welding of dissimilar metals; however, there has been a lack of investigation into the influence of this effect on electron beam welding joint formation and its dependence on test plate thickness. The thermoelectric effect of electron beam welding between GH4169 and Ni with varying thicknesses, as well as the influence of induced magnetic fields on electron beam trajectories, are investigated through the establishment of a numerical model incorporating thermal-electric-magnetic coupling.The results show that when the test plate increases from 2.5 mm to 10 mm the peak current density increases from 5.1 × 106 A/m2 to 7.6 × 106 A/m2, and the maximum magnetic flux density increases from 1.49× 10−2 T to 1.77 × 10−2 T. The increase in magnetic flux density results in a greater displacement of the electron beam spot away from the interface between the two materials, thereby causing incomplete fusion defects in the joints. This study elucidates the fundamental physical principles underlying the occurrence of incomplete fusion defects in electron beam welding joints, thereby furnishing essential theoretical underpinnings for enhancing the quality of dissimilar metal electron beam weld joints.

The effect of friction stir welding on the microstructure and mechanical properties of the dissimilar SS304 and Al7075-T6 alloy joints

This study focuses on the friction stir welding (FSW) of dissimilar materials, Al7075 alloy and SS304 stainless steel, in a butt configuration. The objective is to examine the impact of different operating conditions, including tool rotational speed, transverse speed, and tool offset, on the FSW process of the dissimilar sheets. Mechanical properties, specifically the ultimate tensile strength, were found to be influenced by rotational speed. Higher rotational speed resulted in decreased tensile strength due to increased heat generation in the weld zone, leading to the formation of a thicker intermetallic layer. Higher tool rotational speed and greater transverse feed rate improved weld joint performance. Microstructural changes and deformation properties were investigated using optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The FSW process caused significant grain refinement, creating a fine and equiaxed recrystallized grain structure. Intermetallic compounds like Al13Fe14, Al3Fe2, and Al3Mg2 were identified in the interface zone. In summary, this study provides valuable insights into the FSW of dissimilar materials. It sheds light on mechanical properties, microstructural changes, and intermetallic compound formation in the welded joint, contributing to the understanding of FSW for dissimilar materials.

Fatigue Behavior of Rotary Friction Welding of Acrylonitrile Butadiene Styrene and Polycarbonate Dissimilar Materials.

Understanding the fatigue behaviors of weld joints is significant in engineering practice. Rotary friction welding (RFW) can join the additively manufactured polymer components. Until now, no research has focused on the fatigue behavior of polymer components jointed via RFW. This study investigates the fatigue life of ABS/PC dissimilar components fabricated via RFW and proposes the fatigue mechanism based on the failure structure. This work uses five different cyclic loads and rotational speeds to investigate the fatigue life. The fatigue life of the RFW of ABS/PC dissimilar rods is better compared with the pure ABS and pure PC specimens due to weld and integrity microstructural changes resulting from the combination of ABS and PC materials. The number of cycles until the rupture of RFW of ABS/PC dissimilar components (y) can be determined by the cyclic load (x) according to the prediction equation of y = -838.25x2 - 2035.8x + 67,262. The fatigue life of the RFW of ABS/PC dissimilar components increase with the increased rotational speed. The number of cycles until rupture (y) can be determined by the different rotational speeds (x) according to the prediction equation of y = 315.21x2 + 2710.4x + 32,124.

Analysis of laser welding on dissimilar materials with the influence of adding interlayer

The laser welding of dissimilar materials poses several challenges in practical applications, such as molten pool instability, the formation of intermetallic compounds (IMCs), and cracking caused by differential thermal stresses. In this study, we investigated the impact of incorporating a nickel (Ni) foil as an intermediate layer on lap joints of dissimilar materials (SS304 and Al6061) welded using the continuous laser welding (CLW) technique. The thermomechanical simulation accurately predicted the width and depth of SS304–Ni–Al6061 joints, with deviations of merely 3.92% and 19.04% from experimental results, respectively. Residual stress analysis revealed that the addition of a nickel foil reduced residual stress in the heat-affected zone (HAZ) and improved joint fatigue life. Furthermore, the incorporation of 0.1 and 0.2 mm Ni foils enhanced joint strength and effectively suppressed the formation of brittle intermetallic compounds, resulting in a remarkable maximum lap shear force of up to 1026 N. The simulation results for the shear load-displacement curve displayed excellent agreement with experimental data, with a deviation of only 6%. Notably, joints with the Ni foil demonstrated a greater ability to prevent crack formation caused by thermal expansion mismatch compared to joints without the Ni foil. The Ni interlayer served as a diffusion barrier and stress buffer, promoting a more uniform microstructure and reducing the likelihood of crack formation in bonded materials. Overall, this study comprehensively investigates the impact of incorporating a nickel interlayer on laser-welded lap joints of dissimilar materials. The findings offer valuable insights for practical applications, enabling improved joint strength, reliability, and crack resistance in laser welding dissimilar materials.

Research of the stress-strain state of the loaded assembly for friction welded device

This article presents the results of the study of methods for friction welding of dissimilar materials and the calculations to determine the structural strength of the most loaded part of a special friction welding device were made. The analysis showed that the friction welding method has wide technological capabilities and it is used in various industries. The designs of existing devices and machines for friction welding were also investigated. It was revealed that the method of friction welding in the conditions of machine-building plants of the Republic of Kazakhstan (RK) has not found application due to the little knowledge and high cost of technological equipment. The authors have developed a special device for friction welding of dissimilar materials. To optimize the parameters of the parts, in particular the bracket part, the stress-strain state calculations were performed using the ANSYS software package and the strength calculation by determining the acting external critical loads. The results of the calculation showed the applicability of the developed design of the bracket part.

Significance of the Interlayer in Explosive Welding of Similar and Dissimilar Materials: Review

Significance of the Interlayer in Explosive Welding of Similar and Dissimilar Materials: Review

Friction Stir Welding of Dissimilar Materials with Reinforcement of Copper Particulates

In this study, the controlled input parameters namely welding speed and spindle speed were optimized by Taguchi method for reinforcement of copper particulates in aluminium alloy (AA6061-AA6063-T6). High carbon and high chromium steel i.e. tool steel D2 type material is used as a friction stir welding tool. Subsequently, the effects of the process parameters were investigated. The signal-to-noise ratios and analysis of variance were applied for statistical analysis. The outcome shows welding speed is the significant parameter than spindle speed. Under the optimum process parameters, 1400 rpm with 16 mm/min were shown best values such as 61.60 MPa for ultimate tensile strength and 91 hardness values. It means moderate spindle speed and lower welding speed develop higher heat. Subsequently, it is also shown that the feasibility of signal-to-noise ratio is responsible to improve welding quality after reinforcement.

Pulsed thermo-induction-dynamic welding and pressing of dissimilar materials

To obtain permanent joints from diversified parts and powder compositions, it is proposed to use discharge-pulse processes with the accumulation of stored energy in a capacitor bank. Technological difficulties in the manufacture of structures from non-ferrous metal and alloy parts of different thicknesses are listed. The thermal effect is carried out by passing the discharge current from the batteries of pulse capacitors, and the power effect is realized through the use of an inductive-dynamic drive. A scheme for the series connection of a compacted powder with an induction-dynamic drive, consisting of a flat inductor with a pusher, is proposed. The physical essence of the formation of compounds is described. The processes responsible for the formation of permanent connections by a pulsed current discharge have been identified. A picture of the relationship between the main parameters of the pressing process – sintering in time, as well as the results of measuring the temperature of the sintering process of powders by the photoemission method is presented. The results of energy consumption for the consolidation of powder compositions with simultaneous welding to a steel base are given.

Effect of welding process parameters on surface topography and mechanical properties of friction-stir-welded AA2024/AA2099 alloys

The joining of two materials with different chemical composition was a major setback for conventional methods of metal joining. The results of this welding were showing considerably great improvement in the aspects of quality of weld, amount of heat generated, uniform distribution of material, refined microstructure, enhanced tribology, materials flowing pattern, good strength with reduced internal stresses. Optimized parameters were estimated by using Desirabilty approach and Response surface methodology. Optimum parameter combination for dissimilar material welding was observed to be 913.74 rpm, 45 mm min−1 and 8kN. The desirability values for dissimilar welding process were 0.912 respectively. The grain enhancements were decreased in the range of WC > WT > HAZ > Parent material. The wear rate of dissimilar AA2024 and AA2099 were superior as the wear value increases from 0 to 50 μm in the nugget zone. The coefficient of friction value remains constant throughout the wear experiment ranges from 0.3 to 0.55. A steady state friction value of 3N to 5N is observed when sliding distance increases. The wear loss was measured by finding the difference between initial weight and final weight and found as in the range from 0.2283 g to 0.4866 g.

Advanced Welding of Dissimilar Materials for Aerospace and Automotive Applications

The aerospace and automotive sectors are now experiencing a growing need for lightweight and high-performance components. As a result, there is a significant interest in investigating new welding methods that can effectively fuse different materials. The process of welding different materials poses notable difficulties as a result of disparities in physical qualities, metallurgical attributes, and thermal expansion coefficients. The research starts by examining the rationales for employing diverse materials in various sectors, emphasising the benefits they provide in relation to decreased weight, greater fuel economy, and improved mechanical characteristics. Following this, the study explores a range of sophisticated welding techniques that have arisen in response to these issues. This paper examines several fusion welding techniques, including laser welding, electron beam welding, and friction stir welding. Each approach is discussed in detail, with a comprehensive description of its fundamental concepts. This discussion focuses on the advantages of each approach in relation to the reduction of heat-affected zones, the attainment of precise control over the welding process, and the minimization of intermetallic compound formation. The study also emphasises the use of case studies and practical instances to showcase the effective implementation of sophisticated welding techniques on dissimilar materials. The feasibility and efficiency of these approaches in combining incompatible materials, such as aluminium to steel, titanium to composites, and others, are exemplified by instances observed in the aerospace and automotive sectors.

Effect of friction stir welding parameters on microstructure-based defect formation and mechanical properties of Tailor Welded Blanks

This maiden work on friction stir welding (FSW) of unequal thickness dissimilar (UETD) materials with plate thickness ratio (PTR) of 2.54 presents a comprehensive analysis of the effect of FSW process parameters on mechanical properties and microstructure-based defect formation of tailor welded blanks (TWBs). In contrast with equal thickness butt joints, the thickness mismatch in TWBs creates various challenges in the process requisite, influencing the process mechanics leading to inadequate heat input and improper mixing of base materials, making the joint prone to various defects. Defects such as tunnel defect, kissing bond defect, voids, and incomplete root penetration (IRP) defect observed and discussed comprehensively in this study are largely attributed to the complexities in the process requisites and mechanics, selection of unfavourable combinations of FSW process parameters, variation of plate thickness, and occurrence of surface oxide layers at the abutting surfaces. The present work included and discussed microstructural features around defects, temperature history, and mechanical properties of joints such as tensile strength and hardness to understand the effect of FSW process parameters on failure mechanism of TWBs in detail. Based on the results obtained from mechanical properties of joints discussed in this study, it was revealed that IRP defect deteriorated the mechanical properties the most followed by tunnel defect, kissing bond defect and voids. Figure: Illustrates (a) FSW set up (b) macrostructure of welded joint (c) tensile specimen and (d) specimen indicating positions of microhardness readings