The properties of sintered and heat-treated steels produced from the Catamold 8740 material by powder injection molding were examined. Parts made of the Catamold 8740 low-alloy mild carbon steel are used in the military, automotive, and other industries where high reliability and resistance to dynamic loads are required. The Catamold 8740 chemical homogeneity was studied as a function of powder injection molding parameters: heating rate, sintering temperature, holding time, and subsequent heat treatment. Microscopic analysis showed that Catamold 8740 was a mechanical mixture of powders in various sizes (carbonyl iron, nickel, Fe-Mo, Fe-Cr, Fe-Si-Mo, Fe-Si). When the heating rate of the Catamold 8740 powder mixture increased from 2 to 5 °C/min, the microstructural heterogeneity caused by uneven compaction decreased and the alloy formation process activated at 900-1340°C. The impact strength of Charpy V-notch test samples changed from 10.39 to 11.52 J/cm 2 with higher sintering temperature and heating rate increasing from 2 °C/min (1270°C) to 5 °C/min (1340°C). When holding time increased from 30 to 90 min at a sintering temperature of 1340°C, the material became denser, the pores rounded, and the ferrite matrix homogeneous. However, the impact strength decreased by a factor of 1.4 because of coarser grain sizes and brittle fracture. Heat treatment processes reduced the impact strength after sintering. The results obtained were used to optimize the powder injection molding parameters. The influence of chemical and dimensional inhomogeneity of the starting Catamold 8740 powders and sintering kinetics on the structure and mechanical properties of parts operating under impact loads was established.

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The article is devoted to the problem of political-linguistics education at universities of Ukraine. The place of political linguistics is defined as a new interdisciplinary branch of scientific knowledge. The necessary of learning this discipline is argued at higher education institutions, especially at the postgraduate studies (PhD’s level). The paper touches upon the problem of political discourse determination as the main subject of the political linguistics. Although it is comparatively the young discipline and the definitions of its main categories aren’t universal enough, but the learning of political linguistics and its general components comes actively into educational and scientific syllabuses of Ukrainian higher education. The aim of the article is defining of the main specific principle and features of political linguistics learning at higher educational institutions in Ukraine. Such principles and features depend directly on specific peculiarities of political discourse and the interdisciplinary character of political linguistics. The author analyzes the problem of political discourse understanding as the subject of political linguistics study and the features of its categories representations in different syllabuses. She explores the researches about the learning methodology of political linguistics and of some tangent disciplines at universities of Ukraine.