Microstructure and microhardness of nickel-base heat-resistant alloys obtained by directional and equilibrium crystallization
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Date
2019
Journal Title
Journal ISSN
Volume Title
Publisher
Lviv Politechnic Publishing House
Abstract
In order to determine the safe operational life of the components of gas turbine engines (GTE), introductory tests of nickel-base heat-resistant alloys (NHRA) have been performed. X-ray fluorescence and X-ray diffraction analyzes, optical microscopy and Vickers hardness measurements provided data on the phase-structural state and mechanical properties of the pristine ZhS6K-VI and ZhS32-VI alloys obtained by equilibrium and high-speed directional crystallization, respectively. Almost complete compliance of the investigated materials with the certified alloys in chemical and phase composition has been found. A significant difference in the parameters of the fragments of the microstructure of the investigated alloys, which is naturally consistent with the conditions of equilibrium and high-speed directional crystallizations, was revealed. A slightly lower anisotropy of microhardness (2.8 %), measured in transverse and longitudinal sections, was found in the ZhS6K-VI alloy as compared to the anisotropy (5.1 %) in the ZhS32-VI alloy. The obtained results will be used to test a nondestructive method for determining the safe operational life of gas turbine engine components.
Description
Keywords
heat-resistant alloys, nickel-base superalloys, directional crystallization, equilibrium crystallization, gas turbine, blade, microstructure, microhardness
Citation
Microstructure and microhardness of nickel-base heat-resistant alloys obtained by directional and equilibrium crystallization / Andriy Trostianchyn, Serhii Shvachko, Volodymyr Kulyk, Eduard Pleshakov, Yuriy Molkov, Taras Lenkovskiy // Ukrainian Journal of Mechanical Engineering and Materials Science. – Lviv : Lviv Politechnic Publishing House, 2019. – Volume 5, № 3/4. – P. 33–38. – Bibliography: 17 titles.