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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]

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 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 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]

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 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]