Electron Beam Welding Research Articles

Mechanical & metallurgical properties of dissimilar joining of P91 ferritic steel: A review

Dissimilar joints of P91 ferritic steel and other materials had been widely studied for their potential applications in various industries. The mechanical and metallurgical properties of these joints can be affected by various factors such as the microstructure, composition, and thermal treatment of the materials being joined. The welding techniques and the heat affected zone playing a important role in the properties of the joints. The main concern when joining these dissimilar materials is the interface reaction and stress corrosion cracking. The hardness, tensile strength, fatigue strength, creep strength, and impact toughness of the joints are also important properties that need to be considered. The brittle fracture and diffusion bonding are also important factors that affect the mechanical and metallurgical properties. Tungsten Inert gas welding, resistance spot welding, Laser welding, Electron Beam welding, and other welding techniques have been used for joining P91 ferritic steel and other materials. The properties of the joints produced using these techniques must be thoroughly evaluated to ensure their suitability for specific applications. This review paper is focused mainly on the dissimilar joining of the P91 Ferritic steel its mechanical, corrosion properties and microstructure.

Optimizing microstructure and mechanical properties of Ti-5Al-2Sn-2Zr-4Mo-4Cr alloy electron beam welded joint through post-weld heat treatment

Electron beam welding (EBW) is suitable for joining titanium alloys. However, the utilization of EBW leads to an uneven microstructure within the weldment due to the rapid solidification and non-uniform temperature gradients, which results in the formation of coarse columnar β grains, ghost α phases, and metastable martensite α/α′ phases, decreasing the mechanical properties. Post-welded heat treatment (PWHT) is a practical method of enhancing mechanical properties by changing the phase composition and grain size. PWHT can promote decomposition and recrystallization of the metastable martensite α/α′ phase in the fusion zone (FZ) and heat-affected zone (HAZ), creating dense nanoscale acicular α phases to build α+β colonies. As the holding time and temperature increase, the thickness and spacing of the acicular α phases increase. The increase in acicular α phases thickness and spacing has a more significant impact on the nanohardness but a lesser effect on the microhardness. Optimal PWHT is 630 °C for 2 h, followed by air cooling, which promotes the precipitation of dense nanoscale acicular α phases in the columnar β grains and ghost α phases, resulting in fine-grain strengthening effect, thereby greatly enhancing the mechanical properties of the welded joint with a tensile strength of 1053.8 MPa, an elongation of 14.33%, and a fracture at the base metal (BM). Moreover, due to the formation of dense nanoscale acicular α phases, more grain boundaries are generated, which hinder the dislocation movement, so that the localized strain in the FZ and HAZ is much lower than that in the BM.

Numerical Fatigue Strength curve for the C1 Wedge Connection

AbstractThis paper presents an investigation on the fatigue life prediction of the C1 Wedge Connection based on advanced finite element analysis. Recently developed, this connection links tubular sections of wind turbine towers using small horizontally placed bolts to slide two wedges, which pull the fork‐shaped upper flange and shaft‐shaped lower flange of the tower together. The fork‐shaped upper flange is manufactured using electron beam welding. A 3D finite element model is developed in ABAQUS software to simulate the behavior of the connection. A sequential thermal‐mechanical analysis is performed to simulate the electron beam welding process and estimate the residual stresses and distortions. The crack initiation at the lower flange, where the largest stress range is observed, governs the fatigue resistance of the connection. Fatigue crack initiation is assessed using the strain‐based local approach and code‐based methods such as the EN1993:1‐9 and DNV‐RP C2003. A comparison of the predictions from these methods is presented.

Novel fatigue life prediction method of a Ni-based superalloy welded joint considering defect and temperature

Defects are the primary cause of fatigue failure of welded structures, resulting in high dispersion in fatigue test results. In this study, a rapid fatigue life evaluation model is established, which considered both the effects of initial welding defects and service temperature. Firstly, the mathematical relationship between temperature and Vickers hardness is obtained by fitting a series results of high temperature Vickers hardness tests. Then, based on the SEM fracture morphology analysis of fatigue failure samples, the concept and formula of modified stress considering the information of defect size and position are proposed. Finally, a new life prediction model is established by combining the temperature-hardness relationship model with Murakami's model. The fatigue life of GH4169 electron beam welding joints can be evaluated by this model at any temperature, and most of the predicted results are within a scatter band of ±2.

Investigation on microstructure and mechanical properties of 160mm thick 316L stainless steel electron-beam-welded joint

The maximum thickness of flanging position on the vacuum vessel (VV) window collar of China Fusion Engineering Test Reactor (CFETR) is 160 mm. Electron beam welding can achieve one-time penetration of the thick plate without groove and the deformation after welding is quite small. The cross section of weld was sampled for microscopic observation and mechanical properties tests to explore the difference in microstructure and performances of 160 mm thick 316 L stainless steel electron-beam-welded joints. The results showed that the weld depth-width ratio reached up to 16:1, and the microstructure of weld was composed of ferrite and austenite with different morphologies which was mainly coarse cellular crystal in heat affected zone (HAZ). The equiaxed grain orientation in the root region (denoted as “R region”) was mostly [001] and the columnar grain orientation along the temperature gradient was mostly [101]. The microstructure along the depth direction was quite different, which was mainly related to the solidification mode and composition overcooling. The high strength (YS=715.22 MPa) of R region was due to the smaller temperature gradient and the larger cooling rate, the position of fracture suggested that the strength of weld was higher than that of the base metal. The microhardness measurement results showed that the hardness increased gradually along the depth direction of weld (Top:156.5 HV, Root: 238.7 HV) and fluctuated along the width direction. The tensile properties along the thickness direction exhibited a trend of decreasing first and then increasing, which was mainly related to the characteristics of electron beam deep penetration welding and the difference of grain structure along the thickness direction.

Investigation of microstructure and mechanical properties in dissimilar-metal welding between ferritic stainless steel and Co-based superalloy using electron beam welding

This research investigates the relationship between the microstructure and mechanical properties of electron beam welding joints, with a particular emphasis on the influence of varying electron beam currents on AISI 410L stainless steel plates and NS163 Co-based superalloy wires, which is a rare and novel form of welding. An increase in beam current led to a gradual transformation of the weld microstructure from columnar to equiaxed grains, creating finer and more homogeneous grains. Macrosegregation was also observed, a consequence of the liquidus temperature difference between the weld metal (WM) and base metal (BM). The segregation structure exhibited irregularly shaped beaches near the fusion line and islands of unmixed and partially mixed NS163 within the WM. This phenomenon was more pronounced in samples with a lower beam current. Given the limitations in BM shape and WM size, nanoindentation was employed to characterize the strength of welded joints. In conjunction with microhardness measurements, it was confirmed that the weld is strengthened under different electron beam currents, with higher current resulting in a more significant strengthening effect. This study also underscores the value of nanoindentation in evaluating the weld strength of brush seals without destruction.

Electron beam welding of dissimilar Titanium to aluminium: Interface microstructure and mechanical properties

Welding of dissimilar metals, titanium–aluminium having wide differences in mechanical and thermal properties was highly challenging. In the present investigation, the electron beam welding method was used to join titanium alloy with pure aluminium. The results show that at the optimum parameter levels such as beam current of 6 mA, welding speed of 8 mm/s, and beam offset of 70:30 (Ti:Al) toward titanium, a defect-free joint with the higher mechanical strength of 120 MPa was achieved compared to the other combination of parameters. The percentage contribution of significant parameters was welding speed of 62%, and beam current of 25%. The scanning electron microscope was used to study the Ti–Al interface microstructure in detail. A significant increase in the micro-hardness in the weld zone was due to a change in titanium microstructure from equiaxed α-phase to acicular α and the formation of Ti-Al intermetallics in the fusion zone. X-ray diffraction analysis was used to analyze the phases present in the fusion zone. It was confirmed that there were mainly Al-Ti compounds like Al2Ti, Al3Ti, AlTi, AlTi2, Al11Ti5. These phases are harmful and contributed to higher hardness and brittleness in the fusion zone. At optimum conditions, a defect-free joint without intermetallics was obtained without an increase in hardness in the fusion zone.

High-temperature mechanical properties and microstructure of welded joint in GH4169/IC10 dissimilar nickel-based superalloys by vacuum electron beam welding

Jointing precipitation-reinforced GH4169 and newly-developed IC10 nickel-based superalloy through vacuum electron beam welding (VEBW) has become increasingly attractive for aeroengine's blade and disc. In this study, solution treatments (GH4169 for 980 °C/1.5 h and IC10 for 1180 °C/2 h) was chosen before welding, and different aging treatments (900 °C, 950 °C, 1000 °C, 1050 °C and 1100 °C for 6 h, respectively) were used for eliminating uneven compositions and structures of the GH4169/IC10 welded joint after VEBW method. Through optical microscopy (OM) observations, there are distinct morphological differences between the base metal (BM) and fusion zone (FZ) regions, with the BMs regions mainly being equiaxed and the FZ region mainly being dendritic grains after VEBW. Through scanning electron microscopy (SEM) observations, the carbides are mainly distributed at grain boundaries in BMs, and Ni–Cr–Nb phases are the dominant second phases in the FZs after VEBW. Moreover, the grain orientation is obviously strong in FZs with adjacent {001} orientation by electron backscattered diffraction (EBSD) characterizations. while grain orientation chiefly of BMs presents anisotropy. After heat treatments, the maximum microhardness of the welded joint was obtained after aging at 900 °C (242–258 HV), and the minimum microhardness was obtained after aging at 1050 °C (183–190 HV). Besides, among the aged welded joints, the 900 °C aged welded joint has the best high-temperature mechanical properties (tensile strength for 559 MPa and elongation for 19.3%) through high-temperature tensile tests, owing to the strengthening effect of numerous γ′ and γ′′ precipitates, nevertheless, 1050 °C aged welded joint has lower tensile strength than solution treated welded joint, mainly resulting from the numbers of δ precipitates isolating matrix. Moreover, combined with transmission electron microscopy (TEM) observations, the carbides, γ′, γ′′, and δ precipitates lead to different high-temperature tensile properties of welded joints, the transformation of γ′′ precipitates and coarsening of γ′ precipitate promote fracture crack initiation and propagation along grain boundaries.

Experimental and temperature field simulation study of Inconel 718 surface cladding based on vacuum electron beam heat source

By vacuum electron beam welding machine based on simulation of temperature field of NiCrBSi, experiment was conducted by vacuum electron beam surface cladding (VEBSC). The microstructure and friction wear properties of the specimens were analyzed by scanning electron microscope (SEM), electron backscatter diffractometer (EBSD), microhardness tester and friction wear tester under different welding beam currents (IW), respectively. The results show that the grain orientation in Inconel 718 in the rolled state is very dispersed and consists of equiaxed austenite grains (about 15 μm) with a high number of annealed twins. The internal orientation difference becomes relatively uniform after VEBSC, and a large number of elongated needle-like grains (about 200–300 μm) appear in the surface layer. At the same time, the low angle grain boundary of the clad layer (CL) of the specimen increases and then decreases with the increase of IW. When IW = 18 mA, the specimen surface hardness reaches a maximum value of 632.5 HV, and the friction coefficient is at least 0.25. The wear mechanism after cladding is dominated by plowing and abrasive wear to improve the wear resistance of the material. However, the high temperature oxidizing properties do not change much.

Microstructure and mechanical properties of vacuum electron beam welded joints of Ti/Cu dissimilar metals

Sheets of TC4 titanium alloy and T2 pure copper were joined by vacuum electron beam welding with an offset on the copper side. Optical microscopy (OM) and scanning electron microscopy (SEM) were used to study the microstructure of the welded joint, and the composition of the intermetallic compounds (IMCs) at the reaction layer was studied by energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM), followed by tensile testing to investigate the mechanical properties of the welded joints. The results show that electron beam welding can achieve an effective connection of Ti/Cu dissimilar metals. A multilayer structure composed of an IMCs layer, a final solidification zone, and a weld zone is formed at the Ti/Cu interface. The main composition of the IMCs layer is the faceted phase of TiCu and a small amount of the faceted phase of Ti2Cu, while the FS zone is composed of tiny equiaxed grains of copper. The tensile test results show that the ultimate tensile strength of the joints reaches 190 MPa, and the elongation rate reaches 4.27%. The joint presents brittle fracture characteristics with fracture occurring in the IMCs layer.

Effect of Gap Clearance on Microstructure and Mechanical Properties of Electron Beam Welding–Brazing Ti/Al Butt Joint with Al-Mg Filler Wire

Effect of Gap Clearance on Microstructure and Mechanical Properties of Electron Beam Welding–Brazing Ti/Al Butt Joint with Al-Mg Filler Wire

Electron Beam Welding Process for Ti6Al-4V Titanium Alloy.

The electron beam welding process of titanium alloys induces a series of physicochemical changes in the material that remain a relevant and necessary area of investigation. A necessary step performed after the electron beam welding process of titanium alloys in the Ti6Al-4V grade to mitigate the resulting thermal stresses is the post-weld heat-treatment process conducted through stress relieving. This study presents the comparative analysis results of the mechanical properties and structure of the Ti6Al-4V titanium alloy after electron beam welding and subsequent stress-relieving heat treatment at a temperature of 590 °C for 2 h. The analysis focused on the levels of mechanical properties such as microhardness in the heat-affected zone and weld, tensile strength, and microstructure analysis in the heat-affected zone and weld. The aim of the research was to answer the questions regarding whether the post-weld heat treatment through stress relieving after electron beam welding of the Ti6Al-4V titanium alloy would significantly affect the changes in mechanical properties and microstructure of the alloy and whether the applied welding speed in the study would cause a significant depletion of alloying elements in the material. During the course of the study, it was found that conducting the electron beam welding process at a speed of 8 mm/s resulted in a depletion of one of the alloying elements (aluminum) in the face area. However, the decrease in aluminum content was not significant and did not exceed the critical value of 6% specified in the material standards, which determined the material's application based on its strength properties.

Microstructure and strength of the Ta cladded W targets prepared by electron beam welding followed by hot isostatic pressure

Tantalum (Ta) coated tungsten (W) targets were prepared by hot isostatic pressure (HIP) diffusion welding in the temperature range from 1250 °C to 1550 °C. The mechanical tensile properties displayed that the bonding strength of the WTa interface reached the maximum value of 138.3 MPa at 1450 °C. The value of nanoindentation hardness of the WTa interface are between the values of W and Ta substrates indicating the diffusion layer. WTa diffusion layers were formed during the HIP, and the thickness of diffusion layers increased with the increase of the HIP temperature. TEM results show that the diffusion layer consists of WTa solid solution, and crystal plane distances of the diffusion layers were slightly enlarged due to the WTa solid solution.

A comparison of thermo-mechanically-treated and electron-beam-welded strong, ductile medium-entropy alloy: Microstructural evolution and deformation mechanisms

The microstructure, room-temperature deformation mechanisms, and weldability of the medium-entropy alloy (MEA) NiCoVAl0.2 have been investigated. Defect-free welded joints have been produced with good mechanical properties, indicating excellent weldability. The microstructure consists of f.c.c. grains containing many b.c.c. Ni2VAl (Ni26.1Co33.5V27.8Al12.6) and few σ-type precipitates (Ni15.5Co21.3V62.7Al0.5). Decreasing the aging temperature from 1100 °C to 900 °C, produced a higher area fraction of Ni2VAl precipitates (8 → 25%), much smaller L21 precipitates (7.2 → 1.4 μm), finer grains (17.1 → 2.4 μm), and presence of σ-type precipitate, resulting in simultaneous improvements in both the strength and ductility for both the thermo-mechanically treated (TMT) and electron beam welded (EBWed) MEA. The TMT MEA shows an excellent combination of strength (YS∼993 MPa, UTS∼1478 MPa) and ductility (30.3%), while the EBWed MEA shows slightly lower strength (YS∼822 MPa, UTS∼1194 MPa) and significantly reduced ductility (12.3%), i.e. a YS, UTS, and ductility of 83%, 81%, and 41%, respectively, of those of the TMT MEA. With increasing strain, both low-angle grain boundaries and geometrically-necessary dislocation (GND) densities increased. The TMT MEA has a higher GND density (1.6 × 1015 m−2) than the 9.1 × 1014 m−2 of EBWed MEA after strained to fracture. For both the TMT and EBWed MEA aged at 900 °C, the deformation was accommodated by dislocation slip, dislocation looping around precipitates, and nano-twinning. However, for both the TMT and EBWed MEA aged at 1100 °C, more abundant deformation twinning and an fcc→hcp shear transformation appeared, which may originate from a lower stacking fault energy due to differences in the f.c.c. matrix composition.

Microstructure and mechanical properties of WRe/GH3128 alloy electron beam welded joint

This study investigates electron beam welding of WRe/GH3128 alloy, focusing on the microstructure, defects, mechanical properties, and fracture characteristics of the welded joint. Competitive grain growth within the weld, attributed to solidification rate and grain orientation, as well as the influence of electron beam keyhole oscillation on grain morphology, is analyzed. The study discusses the uneven distribution of solute concentration within the solid phase during the non-equilibrium solidification stage of the weld, along with dendritic segregation and phase transformation processes. Segregation of Cr, Re, and C elements in the interdendritic region results in abundant precipitation of σ phase and M6C. Non-equilibrium solidification phase fractions and phase transformation processes within the weld are calculated using JMartPro software. Furthermore, the potential relationship between the uneven diffusion of elements within the reaction layer and the formation of intermetallic compounds is discussed. XRD testing confirms the presence of Cr7Re3, Ni4W, Ni4Mo, and M6C within the reaction layer. The microhardness and tensile properties of the joints are evaluated, with a tensile strength of 600 MPa, representing 77% of GH3128's strength, while the elongation is only 2.5%. The increase in weld microhardness is attributed to changes in grain morphology and precipitation of M6C and σ phases, with M6C reducing joint plasticity. Cracks and defects are observed in the WRe heat-affected zone, and the role of metallurgical bonding and solid-state healing in crack repair is elucidated. Finally, an analysis is conducted on factors such as crystal microstructure defects that can lead to crack nucleation and propagation, providing separate explanations for intergranular fracture in the WRe base material and brittle fracture in the reaction layer.

Research of Friction Stir Welding (FSW) and Electron Beam Welding (EBW) Process for 6082-T6 Aluminum Alloy.

The paper presents the results of the joining tests of the EN AW-6082 T6 alloy. The materials were joined using the EBW high-energy (electron beam welding) and friction stir welding (FSW) methods. In the case of FSW welding, the following parameters were used: the linear speed was 355 mm/min, and the rotational speed of the welding tool was 710. In the case of EBW welding, the following parameters were used: accelerating voltage U = 120 kV, beam intensity I = 18.7 mA, welding speed v = 1600 mm/min and, in the case of a smoothing weld, U = 80 kV, beam intensity I = 17 mA, and welding speed v = 700 mm/min. Comprehensive microstructural tests of all welded joints (MO, SEM and TEM) and mechanical property tests (tensile and hardness tests) were carried out. The topographies of the fractures after the tensile test were also examined. Based on the results, it was found that the strength properties of the EBW joint were reduced by 23% and the FSW joint by 38% compared to the base material. A decrease in elongation was also noted, with an FSW elongation of 7.2% and an elongation of 2.7% for EBW. In the case of the EBW joint, magnesium evaporation was found in the weld during welding, while in the FSW joint, the dissolution of the Mg2Si particles responsible for strengthening the material during heat treatment to the T6 state was observed.

The influence of electron beam welding technology on mechanical properties of GH4169 welded joints

Super-alloy GH4169 and related welded structures were widely used in the aero-engine industry region. Vacuum electron beam welding is one of the most advanced welding technologies, and the influence of the mechanical property caused by the welding technology still needs further research. Firstly, the hardness, microstructure, and tensile properties of the GH4169 electron beam welded joint were tested. After electron beam welding and two-stage aging treatment, the weld zone was strengthened and its hardness is higher than that of the base metal zone. The microstructure characterization results showed that the grain size of the weld and heat-affected zone was larger than that of the base metal. The tensile results show that the static properties of the welded joint are similar to that of the base metal, and the residual height has no obvious effect on the static strength of the welded joint. The high-temperature creep properties of GH4169 electron beam welded joints with residual height were tested. The results show that residual height will lead to a transient fracture of welded joints under relatively safe service conditions. The fatigue performance of GH4169 welded joints with and without residual height was tested respectively. The results show that the fatigue life of the welded joints without residual height was about 10 times longer than that of the welded joints with residual height under the same stress level, and for the welded joint with residual height, the residual height position will become the main fatigue crack source.

Scale-bridging contrasting and characterization of multi-wire submerged arc welds and electron beam welds in steels

Abstract For a comprehensive microstructural characterization of welds, a scale-bridging analysis of the microstructure is required. It is the only way to identify all microstructural characteristics relevant for the mechanical properties which, in turn, may cover several observation scales. The analytical methods used range from etchings for the macroscopic evaluation of the weld and heat-affected zone to the detection of so-called “local brittle zones” (LBZs) in the micrometre range. This paper will study weld joints in low-alloy steels produced by multi-wire submerged arc welding and electron beam welding. Macro and micro etching as well as electropolishing will be used for microstructural contrasting. Scanning electron microscopy will be performed to identify the finely dispersed carbon-rich secondary phase. Electron backscatter diffraction will enable the identification of so-called martensite/austenite regions (MAs) capable of acting as LBZs.

Investigation on microstructure and mechanical properties of electron-beam-welded joint of reduced activation ferritic/martensitic steel fabricated by selective laser melting

The microstructure and mechanical properties of the complex low-activation ferritic–martensitic components of the China Fusion Engineering Test Reactor (CFETR) were examined in this study. The quenching–tempering treatment of CLF-1 steel formed by selective laser melting (SLM) (referred to as the QTed material) was carried out to analyze the effects of heat treatment on the microstructural and mechanical properties. Meanwhile, the microstructural and mechanical characteristics of CLF-1 steel electron beam welding (EBW) joints after quenching–tempering (referred to as the EBWed material) were investigated. Compared with the untreated sample (referred to as the SLMed material, with an ultimate tensile strength (UTS) = 979.8 ± 12.7 MPa and elongation (EL) = 3.7% ± 0.4%), the quenching–tempering treatment improved the EL of CLF-1 steel effectively (QTed material, 22.3% ± 0.1%), while it decreased the UTS correspondingly (505.6 ± 11.8 MPa), which mainly was due to the change in the grain size and structure during the heat treatment. The special microstructural distribution characteristics of the CLF-1 fabricated via SLM determined that the fracture mechanism was transgranular ductile/intergranular brittle mixed fracture. After electron beam welding of the QTed material, the tensile properties of the joint (UTS = 710.6 ± 21.4 MPa, EL = 9.7% ± 0.1%) were between those of the SLMed and QTed materials. The fracture appeared in the heat-affected zone (HAZ), proving that the strength of the weld was higher than that of the base metal. The microstructure of the weld was almost completely composed of coarse lath martensite, and the accumulation of dislocation clusters, precipitated M23C6-type carbides, and precipitated MX-type carbides contributed to the improvement of the yield strength (YS). The HAZ could be divided into three regions based on the different heating temperatures, and every region had different grain structures composed of mainly martensite and ferrite. The contributions of four strengthening mechanisms to the YS of CLF-1 steel were analyzed quantitatively, which lays a foundation for further improving the performance of CLF-1 steel and improving its application feasibility on the first wall of a fusion reactor.

Electron beam welding of P91 steel and incoloy 800HT and their microstructural studies for advanced ultra super critical (AUSC) power plants

This study characterizes an electron beam welded dissimilar joint between P91 ferritic/martensitic steel and Incoloy 800HT Nickel-based alloy. Such dissimilar metal welds (DMW) have applications in nuclear and thermal powerplants where steam-carrying pipes lead to header sections operating at around 600–650 °C. The study employed an advanced welding process to obtain a clean, high-quality dissimilar metal. The microstructure characterization of the DMW involving Nickel-based alloys is prone to solidification cracking in the weld fusion zone (WFZ), which affects the overall weld properties and leads to failure. In the present study, the WFZ microstructure revealed a mixed solidification mode with a homogenous presence of equiaxed dendritic and cellular-type structures. Advanced analyses of WFZ microstructure were done to account for microsegregation. Nb, Ti, Cr, and Mo microsegregation was found in the WFZ. The Ti-rich grain boundaries in the WFZ provided the pinning action during plastic deformation. The evolution of Cr, Mo-based carbide phases affected the microhardness distribution. Microsegregation under rapid solidification of the WFZ resulted in the formation of secondary phases in the interdendritic region. The effect of the evolution of precipitates deteriorated the mechanical strength. High and uneven dislocation distribution was observed in the WFZ near the IN 800HT weld interface. Under tensile loading, the DMW failed from the IN 800HT weld interface due to coarsening of precipitated in the IN 800HT HAZ region near the weld interface and grain boundary thickening due to the deposition of Ti over them. The tensile strength of WFZ was 592 MPa. The tensile strength of WFZ was 592 MPa. The post-weld heat treatment (PWHT) homogenized the microhardness across the weld. Impact toughness after PWHT slightly increased from 63 J to 69 J. The dissimilar joint obtained using the EBW process had sufficient mechanical strength to be considered for Generation IV power plants under the American Society for Testing and Materials (ASTM) standards. The study concludes that the dissimilar metal welded joint was highly prone to failure despite sufficient strength, as IN 800HT weld interface was susceptible to grain boundary liquation.