All-Russian Scientific Research Institute of Aviation Materials, Moscow, Russia:

E. B. Chabina, Lead Researcher, Candidate of Technical Sciences, e-mail: chabinaeb@viam.ru
A. N. Raevskikh, Postgraduate Student, Grade II Engineer, e-mail: raevskih_anton@me.com
N. V. Petrushin, Principal Researcher, Doctor of Technical Sciences
A. V. Slavin, Head of the Testing Centre at the All-Russian Scientific Research Institute of Aviation Materials, Doctor of Technical Sciences

Made by granules layer-by-layer selective laser melting on single-crystal substrates with crystallographic orientation <001> and <111> nickel-based superalloy ZhS32 structural-phase state at technological process various stages and during the long-term strength tests investigation results are presented. High-temperature homogenizing annealing, hot isostatic pressing and imitating operating conditions influence on the material structure forming and changing was studied. The material has a polycrystalline structure. γ'-phase particles in grains have generally a cubic form, but their orientation and the size differ in different grains. As a result of located on cells boundaries primary carbides dissolution disperse carbides were formed in grain body. Discrete particles — the large extended carbides and γ'-phases chains are located on grains boundaries. Consisting of γ'-phase coarse particles and carbides heterophase structure agglomerates, which size is commensurable with a grains size, are found in the material. During the long-term strength tests at 1050 ^oС temperature γ'-phases continuous cover was formed on grains boundaries. Grains boundaries extent and their disorder on width increase with temperature and tension action time on sample increase. In grains there is carbides additional precipitation, including lamellar morphology carbides. Polycrystalline nickel-based superalloy ZhS32 structure heterogeneity at high temperature and tension simultaneous influence is aggravated.

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