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Analysis of structural variations taking place at the stainless steel (09Cr18Ni10Ti) - bronze (CuBe2Ni) interface obtained by explosive welding was conducted in the current work. The produced weld joint was post heat-treated in the temperature range from 500 to 800 °С. Microstructural characterizations were carried out using optical and scanning electron microscopy. The results of the analysis revealed the presence of 2 zones at the interface: mixing zone of bronze and stainless steel and a diffusion zone. The diffusion processes in the weld joint during heating were studied by the energy-dispersive analysis (EDX). EDX studies revealed that at 800 °С copper contained in bronze completely migrated from the diffusion layer to the mixing zone whereas iron concentration, on the contrary, increased in the diffusion layer. Voids appeared in the mixing zone of stainless steel and bronze due to the difference of diffusion coefficients of basic elements in the composite.

In this study, new multilayer TiAl-based composites were developed and characterized. The materials were produced by spark plasma sintering (SPS) of elemental Ti and Al foils and ceramic particles (TiB2 and TiC) at 1250 °C. The matrix of the composites consisted of α2-TiAl and γ-TiAl lamellas and reinforcing ceramic layers. Formation of the α2 + γ structure, which occurred via a number of solid–liquid and solid–solid reactions and intermediate phases, was characterized by in situ synchrotron X-ray diffraction analysis. The combination of X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) analysis revealed that an interaction of TiC with Ti and Al led to the formation of a Ti2AlC Mn+1AXn (MAX) phase. No chemical reactions between TiB2 and the matrix elements were observed. The microhardness, compressive strength, and creep behavior of the composites were measured to estimate their mechanical properties. The orientation of the layers with respect to the direction of the load affected the compressive strength and creep behavior of TiC-reinforced composites. The compressive strength of samples loaded in the perpendicular direction to layers was higher; however, the creep resistance was better for composites loaded in the longitudinal direction. The microhardness of the composites correlated with the microhardness of reinforcing components.