Welding Of Dissimilar Materials Research Articles

Advancements in Laser Beam Welding for Dissimilar Material Joining: Exploring Weldability Assessment, Challenges, Parametric Influences on the Mechanical–Microstructural Properties in Steel‐Alloyed Metal Combinations

With the growing demands in several sectors such as the automotive, biomedical, construction, shipbuilding, aerospace, and other manufacturing units, employment of welding techniques has observed a rapid boom in recent times. Laser welding technique is one such recent sign of progress in the fabrication field. Laser beam welding is a radiant energy welding process widely adapted to join a variety of metals and nonmetals. The demand for the dissimilar material welding increases with the increase in industrial needs. Several severe challenges need to be overcome to have such dissimilar welded components mainly as the significant difference in melting point, different combinations of mechanical, metallurgical, chemical, and thermal properties. The present approach attempts to study the weldability of steel and its alloys with other metals and parametric effects on mechanical and microstructural properties. The study reveals that the laser beam offset plays a vital role to achieve sound quality welded joint with desirable weld strength. It has been found that 0.32 mm beam offset generates 243 MPa ultimate tensile strength in the 316L to TC4 dissimilar welds. Again, the addition of interlayers also improves the joint strength of both steel‐to‐aluminum and steel‐to‐titanium dissimilar welded joints.

Characteristics of Solidification Cracking for Ni-P Coated Cu-Al5052 Single-Mode Fiber Laser Welds

This study fundamentally examines the characteristics of solidification cracking in Cu-Al5052 single-mode fiber laser welding by utilizing uncoated and Ni-P coated Cu plates for the high durability busbar welding of pouch-type lithium-ion battery packs. Weld solidification cracking was confirmed regardless of Ni-P coating for both weld materials. However, there were differences in the regions of crack occurrence. Unlike the uncoated Cu-Al5052 welds where cracks occurred randomly within the fusion zone, for the Ni-P coated Cu-Al5052 welds, solidification cracks were concentrated near the faying surface of the upper and lower materials, particularly near the fusion line. The effect of the Ni and P components on the solidification cracking susceptibility, i.e., the welding solidification temperature range, was considered. Diffusion-controlled Scheil’s solidification calculations revealed that the mushy zone range enlarged with the use of a Ni coating layer. It was confirmed that an extremely wide mushy zone range of 1060 K was calculated at the solidification cracking region. Furthermore, P was also identified as an element that expands the solidification temperature range based on the Cu-P binary system. Consequently, during the laser welding of Cu-Al5052 dissimilar materials, the behavior of solidification cracking in the welds is influenced by the composition of the coating material and the incorporated composition within the weld fusion zone. Hence, it is necessary to select the optimal coating material and layer thickness considering weld solidification cracking susceptibility.

Development of an Artificial Neural Network Model to Predict the Tensile Strength of Friction Stir Welding of Dissimilar Materials Using Cryogenic Processes

Development of an Artificial Neural Network Model to Predict the Tensile Strength of Friction Stir Welding of Dissimilar Materials Using Cryogenic Processes

Micro-welding of non-optical contact sapphire/metal using Burst femtosecond laser

Recently, welding of dissimilar material, such as transparent material to metal material, is widely used in aerospace, microelectronic packaging, medicine, etc. Ultrafast laser welding provides a new method for high-performance dissimilar material welding, in which the non-optical contact dissimilar material welding has become a new research hot spot. In this paper, we report the effective welding of Fe-36Ni with roughness as high as 1.1 µm to sapphire, which, to our knowledge, is the roughest dissimilar material welding achieved in ultrafast laser. A 238 fs, 1035 nm, 200 kHz Burst mode femtosecond laser (4 sub-pulses with a total energy of 132.5μJ) yields a smooth and uniform interface with a welding strength up to 11 MPa. In this context, the welding performance and mechanism of Burst mode and single pulse mode ultrafast laser are systematically analyzed. The relevant research results are expected to provide theoretical guidance for the welding of high-strength and high-stability dissimilar materials.

Numerical study of refill friction stir spot welding of dissimilar metallic materials using smoothed particle hydrodynamics (SPH)

Numerical study of refill friction stir spot welding of dissimilar metallic materials using smoothed particle hydrodynamics (SPH)

Linear Friction Welding of Similar and Dissimilar Materials: A Review

Linear Friction Welding of Similar and Dissimilar Materials: A Review

Analysis of the dynamic behaviors of molten pool and keyhole for the oscillating laser welding of dissimilar materials stake welded T-joints with a gap

The dynamic behaviors of molten pool and keyhole have the significant effects on weld quality and joint performance. To investigate the circular shaped oscillating laser welding (OLW) of dissimilar materials stake welded T-joints with a gap between the face plate (FP) and web plate (WP), a dynamic model of molten pool and keyhole for the OLW of dissimilar materials stake welded T-joints with a gap is developed and the dynamic behaviors of molten pool and keyhole during the weld formation process are analyzed and discussed in detail. Based on the calculated results, it is found that the laser beam mainly radiates on the front wall of keyhole and the hump is formed on the rear wall of keyhole relative to the moving direction of laser beam at the FP welding stage. At the gap penetration stage, the keyhole opening at the molten pool bottom of FP shows the trumpet-shaped characteristic and the molten pool is divided into the upper and lower parts by the gap. The formed gas cavity is separated and fused with the keyhole several times at the WP welding stage. The gap around the gas cavity is disappeared after the reintegration of the upper and lower parts of molten pool. The depth of molten pool shows the periodic fluctuation characteristic with time and the fluctuation period is nearly the same as the oscillation period of laser beam during the OLW process.

A Study on Laser Welding of Dissimilar Materials between Aluminum and Copper (Ⅱ) - Development of Laser Welding Quality Verification Technique -

The quality management of laser welding is crucial for EV battery manufacturing as it directly affects vehicle safety. However, there is currently no test standard to evaluate the quality of laser-welded structures. Visual inspection and tensile testing have been used to examine the quality of lap joint laser welding. However, it is dangerous to determine the optimal welding parameters only by tensile strength. The aim of this study was to determine the optimal laser welding parameters by conducting tests for various load directions, such as peel, moment, and low-cycle fatigue tests. As a results, in the case of Al/Cu welding that is highly brittle, the peel test demonstrated greater discrimination than the tensile test. In contrast, the moment test was more effective at determining the strength of the local interface joints. Lastly, the fatigue test yielded similar outcomes to the tensile test. It is challenging to completely replace the tensile test results and utilize them independently. Hence, it is recommended to utilize them exclusively as sub-tests to establish the ideal laser welding conditions.

Computational fluid dynamics based multi-species transport simulation of auxiliary energy systems for friction stir welding of dissimilar materials

This research compares auxiliary energy-assisted friction stir welding (FSW) techniques with conventional FSW when joining dissimilar materials. Specifically, it conducts numerical modeling and experimental validation for the effectiveness of plasma-assisted FSW and induction-assisted FSW for DH36 steel and 6061-T6 aluminum alloy. Fully coupled 3D computational fluid dynamics (CFD) models, incorporating the multi-species transport method, were developed, where the species mass fractions of the workpieces are transported through diffusion, convection, and reaction sources for individual species. Based on the temperature validation, the dedicated heat flux based on the rectangular heat flux and Gaussian heat flux distribution were considered for induction coil and plasma arc heating on the DH36 steel side, respectively. The established conventional and auxiliary energy-assisted FSW models were validated against experimentally observed temperature fields and the joints’ material features. Results indicate that the assistance of plasma and induction auxiliary energy sources increased the temperature field, strain rate, and flow velocity without forming stagnant zones on the steel side caused by reduced dynamic viscosity. In plasma arc-assisted FSW, the steel could not extrude effectively from the base steel sheet due to deficient heat and flow velocity input; therefore, defect-prone coarse steel fragments were blended with the Al matrix. In induction-assisted FSW, the uninterrupted steel layer was extruded from the steel side and placed on the Al side, which was caused by enhanced heat build-up and flow velocity. Moreover, induction-assisted FSW achieved symmetric material flow on both advancing and retreating sides, resulting in defect-free welds.

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.