Twinning in [001]-oriented single crystals of CoCrFeMnNi high-entropy alloy at tensile deformation Academic Article uri icon

abstract

  • © 2017 Elsevier B.V. This paper presents research about the tensile deformation behaviour and deformation mechanisms (slip and twinning) in single crystals of the equiatomic Co20Cr20Fe20Mn20Ni20 (at%) high-entropy alloy (HEA) oriented along the [001] direction in the temperature range T = 77–573 K. Classical studies on single crystals of pure metals and their substitution alloys with the face-centered cubic (FCC) structure, with a low stacking fault energy, have shown that deformation twinning in single crystals oriented along the [001] direction does not develop at tensile deformation. In the present paper, extrinsic stacking faults and deformation twinning in the [001]-oriented single crystals of the equiatomic Co20Cr20Fe20Mn20Ni20 HEA were detected under tensile loading at the temperature of liquid nitrogen after a strain of 5%. The critical resolved shear stress for twinning was determined as τcrtw =210 ± 10 MPa. Deformation twinning in the [001]-oriented single crystals leads to an increase in the strain hardening coefficient in comparison with the slip deformation in these crystals at T > 77 K.

author list (cited authors)

  • Kireeva, I. V., Chumlyakov, Y. I., Pobedennaya, Z. V., Vyrodova, A. V., & Karaman, I.

citation count

  • 18

publication date

  • January 2018