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The paper presents the results concerning the influence of wire-arc additive manufacturing process parameters of aluminum-manganese bronze CuAl9Mn2 products on the structure and mechanical properties of the samples. The conducted studies show that with optimal parameters of the printing mode, the values of the tensile strength of the samples vary between 530-557 MPa. The structure of the samples is free of macro defects, pores and discontinuities. When moving away from the substrate, the structure of the samples changes due to the accumulation of heat in the product during 3D printing by the wire-arc additive manufacturing method. [ABSTRACT FROM AUTHOR]

This work deals with metastable and immiscible Cu-Fe alloys with different iron contents with a homogeneous microstructure were successfully prepared. Such a result was achieved using AISI 321 and C11000 steel and the multi-wire electron beam additive manufacturing. The samples under study were of different compositions with steel varying from 10 mass. % to 75 mass. %. The results showed that as the content of the second component increased, the volume fraction of stainless steel inclusions in the copper matrix increased, forming a heterogeneous melt. In the present work, a scheme of convective motion with diffusion elements in the melt pool at simultaneous feeding of two heterogeneous wires was constructed. During the melting process, the material with higher density occupies the lower position, displacing the less dense material to the upper part of the melt pool. Fluid phase separation processes due to surface tension also take place. After solidification, a heterogeneous melt is observed with the inclusion of copper in the steel matrix and steel in the copper matrix. After reheating, typical for electron beam additive manufacturing, secondary phases precipitate out of supersaturated solid solutions through the phenomenon of diffusion. [ABSTRACT FROM AUTHOR]

The paper shows the peculiarities of changes in the structure and properties in the composite material based on aluminum alloy 5056 during friction stir processing with the introduction of 1.5 vol.% pure copper powder. It has been revealed that with small additions of copper powder even starting from a small number of passes by the tool along the machining line a fairly uniform distribution of particles in the volume of the stir zone is achieved. The mechanical properties during machining with the 1st pass are reduced relative to the properties of the base metal. After the 3rd pass, the material properties are already at the level of the base metal properties. After the 4th pass, an increase in strength relative to the base metal is achieved. It is noteworthy that even after 4 passes along the machining line, small amounts of pure copper unreacted with the base metal remain in the structure of the stir zone. [ABSTRACT FROM AUTHOR]

The paper presents the data of optical microscopy of aluminum cast alloy ER4043 fabricated by wire-feed electron-beam additive manufacturing (WEBAM) and samples of composite material made by simultaneous double-wire feed EBAM with the introduction of 5% and 10% of the nickel alloy Udimet-500. The data obtained testify to the complex and heterogeneous structure organization in composite materials made of dissimilar metals with different melting temperatures and densities. The data indicate the presence of non-melting nickel alloy on one side and overheating of aluminum alloy on the other side. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of the transition layer structure of bimetallic samples based on the nickel heat-resistant alloy Udimet500 and the heat-resistant bronze CuCr1. When printing the bronze part on top of the nickel part, the nickel is melted and kneaded into the bronze part at a distance of up to 5 mm. When printing the nickel part on top of the copper part, the size of the transition zone does not exceed 2-2.5 mm. No cracks or discontinuities were detected at the boundary of the nickel and bronze areas. In the transition zone due to the formation of fine grain structure reinforced by nickel alloy particles the mechanical properties of the bronze increase, resulting in the destruction of samples outside the boundary part inside the bronze. [ABSTRACT FROM AUTHOR]

In the work samples of composite materials were obtained by two-wire printing by electron beam additive manufacturing. In the process of obtaining the samples the peculiarities of the composite structure and typical areas of localization of the intermetallic phases and solid solutions formation were determined. It has been revealed that the formation of continuous large intermetallic interlayers produces defects in the form of micro-and macroscopic sized cracks. According to X-ray diffraction analysis, the main intermetallics in the samples are Cu9Al4, Cu4Al and Cu3Al. Forming intermetallic phases of various types can be localized at the grain boundaries, form honeycomb structures and continuous layers. [ABSTRACT FROM AUTHOR]

The paper presents the results of experimental work on the development of the technique for obtaining composite material on the basis of aluminum-manganese bronze CuAl9Mn2 with the introduction of 5-25% of the nickel alloy Udimet500 during printing. The results obtained testify to a high degree of applicability of the two-wire electron-beam printing technology to composites of the bronze-nickel system with different contents of strengthening phases. There were no defects in the form of cracks or delaminations in the samples. The defect-free structure was obtained by empirical selection of printing process parameters and geometry of wire input into the melt bath. Increasing the volume fraction of the input nickel alloy resulted in an increase of the tensile strength up to 700 MPa. Intermetallic NiAl and Ni3Al as well as M23C6 carbides formed in the structure in large amounts. Also particles with a complex structure of intermetallides and carbides were found. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of the structure organization in composite materials based on copper and copper alloys when produced by electron beam additive technology with the adding of hardening phases using two-wire feeding and with the combined feeding of wire and powder. The conducted studies show the differences in the structure organization and typical defects depending on the way of hardening phases introduction. It is shown that both methods of composite material formation have a number of advantages and disadvantages. [ABSTRACT FROM AUTHOR]

This work obtained a hardened surface layer on the surface of 4Cr9Si2 steel in the process of additive electron beam 3D-printing with the combination of wire and powder feeding of the material into the printing zone. It is revealed that tungsten particles after printing are located mainly in the interdendritic space of the steel. A number of macroscopic inhomogeneities are present in the layer volume. A small-sized transition zone with a mixed structure is formed along the contour of fine powder particles. The orientation of growing dendrites both in the base metal and in the hardened layer has a pronounced direction in the direction of heat removal from the melt bath of each layer. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of the influence of the degree of mutual solubility of metals and alloys in obtaining composite materials with a metal matrix on the organization of the structure. The studies show that for materials with different degrees of mutual solubility of components the organization of the structure differs significantly, which must be taken into account when making products with composite structure. Samples based on components with limited mutual solubility are most susceptible to cracking, especially with excessive formation of intermetallic phases. When obtaining composite materials based on alloys, formation of secondary phases is possible not between the main components, but between the alloying elements. The melting temperature and density of the components, which additionally determine the structure organization of the samples, also have a significant influence when obtaining composites. [ABSTRACT FROM AUTHOR]

In the present study, investigation of the structure of the dissimilar connection of steel and titanium alloy produced by the friction stir welding has been carried out. The welding process modes were also selected. It is shown that layer of intermetallic compounds was about 2 micrometers. Also there were indicated intermetallic types like FeTi and Fe2Ti. Besides, it is shown absence of interaction material of the tool and materials of welded plates. [ABSTRACT FROM AUTHOR]

In this work, CuAl9Mn2 + W100% composite was obtained using electron-beam additive technology. The macro and microstructure of the obtained composite material was investigated. It has been shown that tungsten does not dissolve in the α-Cu solid solution and is formed in the form of agglomerates. It is shown that hardness values increase from the top of the sample to the substrate with characteristic peaks of tungsten agglomerates. The mechanical properties of the printed CuAl9Mn2 alloy and CuAl9Mn2 + W100% composite material were compared. The anisotropy of mechanical properties has been revealed. [ABSTRACT FROM AUTHOR]

In the current work, samples of functionally graded materials based on steel and copper were obtained by wire-feed electron beam addition technique. The samples presented were characterized by a sharp and a smooth interface. To form the sharp interface, it was necessary to change the wire-feed from AISI 321 to C11000 immediately after finishing the N layer pass. Structure formation occurred through convective mixing and primary crystallization. Thus the formation of mechanical mixture on both sides of the sharp interface of functionally gradient material is observed. The width of the sharp interface does not exceed 100 µm. In order to form a smooth interface in the structure between the parts, it was necessary to gradually increase the feeding speed of the copper wire to the molten pool and decrease the feeding speed of the steel wire until it stopped completely. Structure formation in the material occurs through recrystallization and the formation of diffusion volumes, which leads to the presence of solid-phase diffusion. The width of the smooth interface between the components is from 6 mm, and this value can be increased by varying the wire feed rate ratios. [ABSTRACT FROM AUTHOR]