TY - JOUR

T1 - The Use of Hard and Soft Sphere Models for the Evaluation of Lattice Distortion in B2 High-Entropy Shape Memory Alloys

AU - Реснина, Наталья Николаевна

AU - Беляев, Сергей Павлович

AU - Поникарова, Ирина Викторовна

AU - Андреев, Владимир Александрович

PY - 2024/4/1

Y1 - 2024/4/1

N2 - Abstract: This paper considers the application of two known models for the evaluation of distortion in high entropy shape memory alloys with the B2 structure. Distortion was calculated using the hard sphere and soft sphere models for binary TiNi and senary Ti-Hf-Zr-Ni-Cu-Co alloys with different chemical composition. It was shown that both models could not be used because they gave a high distortion value even for binary Ti49Ni51 alloy. Distortion was so large for all alloys that they must be amorphous. However, this contradicted the experimental data according to which all alloys were crystalline with the B2 structure. A modification of both models was proposed taking into account that the TiNi alloy is an intermetallic compound. The formation of intermetallic compound was accompanied by a change in the spatial distribution of electron density around the nuclei of interacting atoms, which led to a change in the atomic sizes. The proposed modification gave the distortion value that was consistent with the lattice stability criterion for alloys where the concentration of each alloying element did not exceed 5 at %.

AB - Abstract: This paper considers the application of two known models for the evaluation of distortion in high entropy shape memory alloys with the B2 structure. Distortion was calculated using the hard sphere and soft sphere models for binary TiNi and senary Ti-Hf-Zr-Ni-Cu-Co alloys with different chemical composition. It was shown that both models could not be used because they gave a high distortion value even for binary Ti49Ni51 alloy. Distortion was so large for all alloys that they must be amorphous. However, this contradicted the experimental data according to which all alloys were crystalline with the B2 structure. A modification of both models was proposed taking into account that the TiNi alloy is an intermetallic compound. The formation of intermetallic compound was accompanied by a change in the spatial distribution of electron density around the nuclei of interacting atoms, which led to a change in the atomic sizes. The proposed modification gave the distortion value that was consistent with the lattice stability criterion for alloys where the concentration of each alloying element did not exceed 5 at %.

KW - configurational entropy

KW - distortion

KW - intermetallic compound

KW - multicomponent alloys

KW - shape memory alloys

UR - https://www.mendeley.com/catalogue/7c962e80-43ef-3030-a8d5-534bf3aa4c34/

U2 - 10.1134/S1029959924020024

DO - 10.1134/S1029959924020024

M3 - Article

VL - 27

SP - 124

EP - 132

JO - Physical Mesomechanics

JF - Physical Mesomechanics

SN - 1029-9599

IS - 2

ER -