Effect of preliminary high-energy ball milling on the structural-phase state and microhardness of Ni3Al samples obtained by spark plasma sintering

The study of the influence of the duration of preliminary high-energy ball milling on the features of the structural-phase state and the level of microhardness of consolidated Ni3Al samples obtained by the method of spark plasma sintering has been carried out. It was found that the inhomogeneous state of the precursor from the 3Ni-Al powder mixture in the case of preliminary ball milling of a short duration (1 min) is a cause of the formation of an inhomogeneous structural-phase state of the consolidated Ni3Al sample. An increase in the duration of high-energy ball milling provides a homogeneous phase compo-sition, promotes the refinement of the grain structure and an increase in the microhardness values of the obtained Ni3Al samples. The main factors determining the processes of structural-phase transforma-tion during the formation of Ni3Al under the conditions of spark plasma sintering, depending on the pre-liminary high-energy ball milling, are revealed. It is shown that grain boundary strengthening is the one of the effective mechanisms for increasing the strength of the material under study.(c) 2022 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

Automated summary

The study investigated the influence of the duration of preliminary high-energy ball milling on the structural-phase state and microhardness of consolidated Ni3Al samples obtained through spark plasma sintering. It was found that short-duration ball milling resulted in an inhomogeneous structural-phase state, while an increase in the milling duration led to a homogeneous phase composition, refined grain structure, and increased microhardness. The study also identified grain boundary strengthening as an effective mechanism for enhancing the material's strength.