4.7 Article

A stored energy analysis of grains with shear texture orientations in Cu-Ni-Si and Fe-Ni alloys processed by high-pressure torsion

期刊

JOURNAL OF ALLOYS AND COMPOUNDS
卷 864, 期 -, 页码 -

出版社

ELSEVIER SCIENCE SA
DOI: 10.1016/j.jallcom.2020.158142

关键词

Cu-Ni-Si alloy; Fe-Ni alloy; High-pressure torsion; Shear texture; Stacking fault energy; Stored energy

资金

  1. National Science Foundation of the United States [DMR-1810343]
  2. European Research Council, Belgium under ERC [267464-SPDMETALS]

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Experiments were conducted to evaluate the evolution of stored energy in grains in Cu 2.5Ni 0.6Si and Fe-36Ni (wt%) alloys after high-pressure torsion (HPT) processing. Different shear texture orientations and components were observed in the two alloys, with varying trends in stored energy evolution with increasing HPT turns. This evolution is analyzed in relation to initial textures, dynamic recrystallization, grain refinement mechanisms, and differences in stacking fault energies.
Experiments were conducted to evaluate the evolution of the stored energy in grains with shear texture orientations A(1)* {111} <<(1)over bar>(1) over bar2 >, A(2)*{111} < 1<(2)over bar>1 >,A {111} < 1<(1)over bar>0 >, (A) over bar {111} < 0<(1)over bar>1 >, B {112} < 1<(1)over bar>0 >, (B) over bar {112} <1<(1)over bar>0> and C {100} < 110 > for Cu 2.5Ni 0.6Si and Fe-36Ni (wt%) alloys after high-pressure torsion (HPT) processing up to 10 turns at ambient temperature using a Kernel Average Misorientation (KAM) approach. A typical stable shear texture developed in the Cu-2.5Ni-0.6Si alloy immediately after 1 turn whereas there was a continuous transformation of texture in the Fe-36Ni alloy up to 10 turns. The results show that HPT processing produces similar stored energies of similar to 35 J/mol and similar to 24 J/mol but with different shear texture components for the Cu-2.5-Ni-0.6Si and the Fe-36Ni alloy, respectively. The stored energy in all shear components for the Cu-2.5Ni-0.6Si alloy increases with increasing HPT processing up to 1 turn and then slightly decreases through 10 turns. By contrast, the stored energy of the Fe-36Ni alloy continuously decreases with increasing numbers of HPT turns. These evolutions are examined with reference to the initial textures, dynamic recrystallization, grain refinement mechanisms and differences in the stacking fault energies. (C) 2020 Elsevier B.V. All rights reserved.

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