This work presents the results of the electron-beam welding of commercially pure α-Ti (CP-Ti) and Ti6Al4V (Ti64) alloys. The structure and mechanical properties of the formed welded joints were examined as a function of the power of the electron beam. The beam power was set to P₁ = 2100 W, P₂ = 1500 W, and P₃ = 900 W, respectively. X-ray diffraction (XRD) experiments were performed in order to investigate the phase composition of the fabricated welded joints. The microstructure was examined by both optical microscopy, scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The mechanical properties of the formed joints were studied using tensile test experiments and microhardness experiments. The results of the experiments were discussed concerning the influence of the beam power on the microstructure and the mechanical properties of the weld joints. Furthermore, the practical applicability of the present method for the welding of α-Ti and Ti64 was also discussed.

This work presents the results of an investigation into the influence of beam offset on the structure and mechanical properties of electron-beam-welded joints between Ti6Al4V and Al6082-T6 alloys. The experimental procedure involved the use of specific technological conditions: an accelerating voltage of 60 kV, an electron beam current of 35 mA, a specimen motion speed of 10 mm/s, and a beam offset of 0.5 mm towards both alloys, as well as welding without an offset. The phase composition of the joints was analyzed using X-ray diffraction (XRD). The microstructure and chemical composition of the seams were studied by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results obtained for the structure of the joints show that the beam offset has a significant influence on the structure. The microhardness was studied by means of the Vickers method. The results for the microstructure showed that the welding procedure without offset and with an offset towards the Ti alloy leads to inhomogeneous welded joints with a significant amount of intermetallics. The offset towards the Al alloy leads to the formation of a narrow area of TiAl₃ phase. The measured microhardness corresponds to the increased amount of intermetallics in the case of offset towards the Ti alloy, with which the highest values were presented (about 58% higher than with Ti6Al4V plate). The results obtained for tensile properties show that the offset to the Al6082-T6 alloy leads to the highest values of tensile strength (TS) and yield strength (YS), which are twice higher than in welding without offsetting of the electron beam.

In this study, we present the results from electron-beam welding operations applied on copper and Al6082T6 aluminum alloys. The influence of beam-scanning geometries on the structure and mechanical properties of the welded joint is studied. The experiments were conducted using a circle oscillation mode with an oscillation radius of 0.1 mm and 0.2 mm. The beam deflection was set to 0.4 mm with respect to the side of the aluminum alloy, and the beam power was set at 2700 W. The phase composition of the obtained welded joints was studied by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was used for the investigation of the microstructure of the joints. The chemical composition was investigated by using energy-dispersive X-ray spectroscopy (EDX). The mechanical properties were studied by micro-hardness investigations. The fusion zone of the weld seam contains three phases—an aluminum matrix, an ordered solid solution of copper and aluminum in the form of CuAl₂, and pure copper. Electron beam-scanning geometries have significant influences on the structure of the weld. Increasing the beam oscillation’s radius leads to a decrease in intermetallic phases and improves homogeneity. The measured microhardness values in the fusion zone are much higher than the ones measured in the base metals due to the formation of intermetallic phases. The microhardness of the weld joint formed using an oscillation radius of 0.2 mm was much lower compared to the one formed using an oscillation radius of 0.1 mm.

In this study, we present the results of electron-beam welding of joints with 304-L stainless steel and copper. The influence of the beam’s power on the structures and mechanical properties of the welded joints was studied; the experiments were realized at a beam deflection of 0.3 mm to the Cu plate and beam powers of 2400, 3000, and 3600 W. The phase compositions of the obtained welded joints were studied by using X-ray diffraction (XRD); the microstructure and chemical composition were investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively. The mechanical properties were studied by using tensile experiments and microhardness investigations. The phase compositions of the welded joints were in the forms of substitutional solid solutions between Fe, Cu, and pure copper and remained unchanged in terms of power. It was found that the microstructures changed gradually with the application of different values of the power of the electron beam. The results of the tensile tests showed higher tensile strengths at lower beam powers (i.e., 2400 and 3000 W) that dropped at 3600 W. The relative elongations rose with increases in the power of the electron beam. Moreover, it was found that the microhardnesses strongly depended on the applied technological conditions (defined by the electron beam’s power) and the corresponding microstructures of the welded joints.

The current work is based on investigating the influence of different technological conditions of electron-beam welding on the microstructure and mechanical properties of joints between Ti6Al4V and Al6082-T6 dissimilar alloys. The plates were in all cases preheated to 300 °C. Different strategies of welding were investigated such as varying the electron-beam current/welding speed ratio (I_b/v_w) and applying a beam offset towards the aluminum side. The heat input during the experiments was varied in order to guarantee full penetration of the electron beam. The macrostructure of the samples was studied, and the results indicated that using a high beam power and a high welding speed leads to an increased formation of defects within the structure of the weld seam. Utilizing a lower beam current along with a lower welding speed leads to the stabilization of the electron-beam welding process and thus to the formation of an even weld seam with next to no defects and high ductility. Using this approach gave the highest ultimate tensile strength (UTS) of 165 MPa along with a yield strength (YS) of 80 MPa and an elongation (ε) figure of 18.4%. During the investigation, improved technological conditions of electron-beam welding of Ti6Al4V and Al6082-T6 dissimilar alloys were obtained, and the results were discussed regarding possible practical applications of the suggested approach along with its scientific contribution to developing further strategies for electron-beam welding of other dissimilar alloys. The downsides and the economic effect of the presented method for welding Ti6Al4V and Al6082-T6 were also discussed.

In this work, the results from the electron beam welding of copper and Al6082T6 aluminum alloy with a titanium filler are presented. The influence of the filler on the structure and mechanical properties of the welded joint is studied in comparison with one without filler. The X-ray diffraction (XRD) method was used to obtain the phase composition of the welded joints. Scanning electron microscopy (SEM) was used for the study of the microstructure of the welds. Energy-dispersive X-ray spectroscopy (EDX) was applied to investigate the chemical composition. The mechanical properties were studied by means of microhardness measurements and tensile tests. A three-phase structure was obtained in the fusion zone consisting of an aluminum matrix, an intermetallic compound CuAl₂, and pure copper. The application of Ti filler significantly decreased the amount of molten copper introduced in the molten pool and the number of intermetallic compounds (IMCs). This improved the strength of the joint; however, some quantity of IMCs was still present in the zone of fusion (FZ), which reflected the microhardness of the samples. The application of a titanium filler resulted in refining the electron beam weld’s structure. The finer structure and the reduced amount of the brittle intermetallic phases has led to an increase in the strength of the joint.