The work is devoted to a study of the microstructure and microhardness of the heat-resistant nickel-based superalloy 58Ni-Cr-Mo-B-Al-Cu after radial-shear rolling. The radial-shear rolling was carried out at a temperature of 925°С in three stages. It was found that the grain size of γ-phase after all rolling stages decreased in the radial direction from the center to the periphery from 62 ± 2 to 2.5 ± 0.2 µm. At the third rolling stage, the grains size was reduced twice in the billet center in a comparison to the initial state. At the same time, individual grains with a size of 100 μm in the billet surface are observed, and grains with a size of 1±0.1 μm are present at the periphery. The microhardness changes in inverse proportion to the grain size, the values increase in the radius direction. The maximum microhardness value is achieved in the peripheral part of the sample and is equal to 5.4 ± 0.6 GPa. According to the EBSD analysis, there is no texture at the billet periphery, but at the middle of the radius there is a two-component axial texture of the <001> + <111> type along the billet axis. The billet center is characterized by the presence of a more pronounced two-component axial texture of the <001> + <111> type along the billet axis. The obtained results indicate the possibility of the gradient structure formation by radial-shear rolling in the heat-resistant nickelbased superalloy 58Ni-Cr-Mo-B-Al-Cu with the initial coarse-grained structure.

It is shown that formation of ultrafine-grained structure in EK61 superalloy up to grain sizes less than 1 μm provides to realize superplastic properties. The influence of deformation in the temperature range 600-1100 °C and strain rate range 10-4s-1– 10-3s-1on the microstructure and properties of ultrafine-grained nickel-based alloy EK61 is studied. It is established that in temperature range 750-900 °C the alloy demonstrates superplasticity (SP) characteristics: strain rate sensitivity factor “m” correspond to 0.39-0.59, stable structure and low changes in the form and size of grains. The maximum SP is displayed at temperatures of 800 °C, wherein the elongation is 1431 %. It has been experimentally confirmed that the use of low-temperature superplasticity is a promising for processing sound solid phase joints by pressure welding of similar and dissimilar Ni-based superalloys.

Experimental modeling of ball lightning (BL) interaction with window glasses has been made with a help of tree types of experiments where metallic spiral heated by a current and laser irradiation heated the window glass. ParametersofBL interaction with the glass at which could appear fractures leading to falling out of gall fragments have been determined.